Nearly two months with the seagrass now

[Samala]

Just a little FYI for anyone interested, I posted a seven week (really two month) update to my website for the seagrass tank. I solved my pH issues and the grass pulled through quite a bit of inattention the last week or so when I was on vacation. Its really starting to look good.. though I was hoping the shoal grass would have filled in a bit more by now. So far I count about fifteen new plants total from shoal grass, one new manatee grass plantlet, and oh.. maybe a hundred or more stargrass leaf sets.

Now I just have to sit back and make sure the whole system is stable and then I can go about adding in the rest of the biosphere.. snails, maybe a few more grass shrimp, and those lovely dwarf seahorses. That will undoubtedly cause a milion new problems to solve, so I'm in no rush at the moment. ;) Enjoy.

Seven week update (http://home.comcast.net/~slardizabal/seagrass10.html)

Oh and I found a super cool website on seaweed, not sure its posted elsewhere here: http://seaweed.ucg.ie/defaultsaturday.html

>Sarah

[ozadars]

Looks gorgeous Sarah :thumbsup: Good Luck!

[piercho]

You're getting a dense growth compared to me. I only supplement with iron and that is probably the difference. I could not keep the stargrass and the rabbitfish both in the main tank. So the stargrass is in the sump. Its the only seagrass the rabbitfish has aggressively grazed and he seems to like it all - including the rhizomes. I've got a new algae that sprang up from the sand you sent me. Its a delicately branched red and I haven't tried to identify the genus. Rabbitfish likes it too, and its only appearing in the sump. May turn out to be an easy refugia algae for those who keep macros as vegetative filters, so I'm trying to keep it going. My turf scrubber seems to have collapsed most of the alga I used to keep, so I'm interested in this one which seems to be surviving in fairly lean conditions.

Thanks for the seagrass and sand and keep up with your postings!

[Samala]

Selim - thanks! I wish my pictures of it were better because they just dont do it justice.

Howard - good to hear from you! I'm intrigued with the finely branching red macro that came from nowhere..... I have none of it in my tank and I was trying to encourage algae growth for awhile. But in comparison to your tank, mine would certainly be nutrient dense. Its a small tank of course, so dosing various oddities like nitrate, phosphate, some B vitamins and bicarb isnt a big deal. ;) Probably doesnt get a chance to get a foothold in competition with the 'grasses.

Thinking back on the collection trip though.. I do remember big swathes of a red algae in the Canal area that had a branched appearance. I just wrote it off as some Gracilaria variant.. I really should learn some macro ID.

At least you kept the foxface, even if the stargrass had to move. :) Shame Halophila is tasty.. I wonder if some of the other grazers would like it too, tangs maybe? I got ahold of a scrawny peice of H. decipiens this past week, so I'm babying it in a separate tank. Hopefully that will get going well too.

I was wondering, for anyone I've sent the stargrass too, have you seen some of the new leaf growth turn a red/maroon? I thought at first it was due to high light conditions, and then perhaps some sort of reaction to pH or O2 balance... and now I have no idea! It will go back to bright green in a few days. Not all the new growth does this, just a few, almost in batches. Thoughts?

>Sarah

[piercho]

No red leaves here, and its under fairly intense light.

Where did you get your copepod culture and what reference are you using for the culture? I thought that copepods were one of the harder cultures to keep going, at least compared to artemia or rotifers. Is it possible to collect a single strain of copepods from the tank and culture that?

I'm asking because I've been trying to bring fang blenny pairs into my tank and having a hard time keeping them fed before they transition to prepared food. If they don't eat they go downhill fast. I'd like to try a dense culture of copepods as Grammarus are too big and I'm not sure they can catch Mysis.

[Samala]

Well I got my copepods from Paul Sach - http://www.aquaculturestore.com. Its a mix of several kinds of calanoid type copepods, dominated by one species from what I can tell under a scope its very likely to be Arcatia genus, I'm hoping its Arcatia tonsa as another seahorse keeper uses them with lots of success. I think, if you're willing to pay for it, you could certainly find a supplier that does pure cultures of a single species, or you could go to the trouble of sorting them yourself. I havent tried picking pods out of my tank to try to start a culture, but that sounds like an interesting distraction I may try this week. :D

References using for culture..... I think a mix of advice from the breeders forum here and articles on Advanced Aquarist and RK mags. Basically a few 2l Coke bottles with slow bubbles and dosing phytoplankton heavily enough so that the bottles are tinged green. Keeping the cultures 'clean' is a bit of a pain and requires dedicated equipment. I'm especially careful about not-touching any of that equipment to the main tank which has all sorts of micro-life that I'm sure would love to take over the copepod cultures.

Gammarus are easy to culture, but if they're too big its not worth it. Mysis is the worst.. they're cannibalistic so if you dont sort out the babies you're just feeding the adults! ;) Any q's shoot em back. I'll try posting those reference articles tonight if I find them.

>Sarah

[Plantbrain]

Sarah-

The red color is low NO3 levels.
Many plants turn redder if you reduce N levels.

If you keep the NO3 at very low or zero for too long, this will hurt the plants.

The plants will use the CO2 from the air if you added a skimmer, but use it as an aeration device rather than for nutrient export, with plants, you will get little anyway, but the skimmer will add CO2 to the water just fine. With higher density of weeds, you'll find you'll need to do this. I added CO2 and compared it with aeration with a skimmer. They were pretty much equal, I had higher plant density than you. All plants/algae prefer CO2 over bicarb.

You should see more growth as a result of aeration.
Adding baking soda for KH should be fine.
KNO3 for NO3.
KH2PO4 for PO4
Most any trace mix
Ca++

That will pretty much cover you.
Note the plant growth after a water change, try large water changes also.

You can also check to see hiow much NO3 is being removed via bacteria. PO4 will preciptate out and complex, plants also take up luxury consumption.

Plants are not entirely to blame.
Also, calibrate the test kits, cheaper kits are notoriously inaccurate.

You can make a standard reference solutions by adding a know weight of say KNO3 into a known volume of water in liters.
See any dosing calculator to find the amount you want.

and if you want to see the weeds growing in nature, come on down to Key Largo on 12-14th of July.

Regards,
Tom Barr

3rd annual Plant Fest July 8-14th 2005!
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[Samala]

Wow.. thanks Tom! Great advice as always. I have never before seen the red leaves = low NO3 connection before. But it fits perfectly with my tank and is probably the most reasonable explanation.

I have been making reference solutions out of KNO3 to be sure I was getting an accurate picture from the test kits.. but since I started using Lamotte I was hoping it was accurate enough to begin with.

Interesting that you mention a skimmer, I just started using one and have had practically no skimmate to speak of, the plants have definitely perked up. More access to CO2 is likely, not just stable Alk levels from dosing sodium bicarb.

I dose everything you mention, in addition B vitamins, which I added just on a whim and it didnt seem to hurt anything so I continued with it. ;) But thats not very scientific.. so..

Oh and I'm seriously considering Plant Fest.. hopefully I'll know my summer rotation schedule soon enough that I can sign up before all the spots are gone. Thanks again Tom.

>Sarah

[Plantbrain]

The red coloration, typically from carotenoids, anthocyanins possess no nitrogen. The green color, is from cholorophyll, a very N rich ring.

Remove a fair amount of green pigment (N limitation) and you are left with?
Reds.

You will find the skimmer will stabilize the KH for you which will provide for easier long term growth, and yes, not much skimmate will be produced with marine plants.

That's often the point for many folks using refugiums, but as you increase the biomass to tank ratio, then CO2 limitation becomes an issue and the weeds go after the HCO3.

You should see a difference in growth rates, reduced micro algae, less KH loss by adding aeration.

You can add CO2 with little negative impact, but it's easier to add a cheap skimmer.

Regards,
Tom Barr

[Fredfish]

Wow, great reading!

I had always assumed that because vascular plants have root systems, they absobed their nutrients through the root system and relied on high nutrient substraits. Is this not the case for seagrasses?

Fred.

[Samala]

It doesnt seem to be the case for any aquatic plants. Some are more root feeders than others, these tend to be plants that periodically are left out to dry when rivers recede after flood seasons (such as in the Amazon system) and encounter some times of being terrestrial plants. But it seems that all of them, in general, will pull their necessary nutrients out of the water column if they cant get it in the soil. (Or, perhaps, if its just easier to access in the water column.) The freshwater crowd talks about substrate or root feeding in the form of tablets/sticks. There was a school of thought that if you only fed the substrate and not the water column, you could keep the nutrients away from the nuisance algaes so they wouldnt grow. But most people just stick to a balanced nutrient management approach to squeeze out the microalgaes.

You could just use a nutrient rich substrate and not dose any nutrients at all, but I suspect that would lead to really slow, sparse growth out of the plants. Which is fine if thats what you want. ;) You might battle more microalgae outbreaks if you aren't skimming heavily to eliminate some of the other DOCs or can get the nutrients out of the system some other way (macroalgae's or live rock, etc.).

Really, all I can say is that my current tank sucks up all the N and P I toss in, as well as Ca and Mg.. and Fe. If I'm not entirely meeting their needs through water column dosing then they're scavanging the mud bottom for the rest of their needs.

Did you ever get your flow-dispersal gadget to work? I'd love to see one in action. :D

>Sarah

[cdi919]

what temp do you keep your tank? can the grasses be kept in a tank at 68*f? i want to keep south african sea horses and wanted to know if the grasses can survive the cooler water.

[Plantbrain]

SeaGrass should be okay at 68F.

SeaGrasses will obtain some DIC from the sediment, but a lot of organic matter is breaking down through bacterial mediated processes and respiring CO2, this is taken in by the plants and in some cases, asorbed by the roots in the sediment.

Most seaGrass beds are highly anaerobic, not much CO2 when breaking down the Carbon, you need O2 for that.

Vascular plants will remove nutrients from the water column given a choice.

When the nutrients become limiting in the water column as is often the case, then they increase root growth and try to get it there.

Many folks assume that since many plants get most of their nutrients from the substrate or have large roots systems, they prefer nutrients in the substrate.

But this is an assumption and merely a corrleation of an observation in natural systems.

Natural systems are generally limiting in terms of a nutrient/s.
When you provide non limiting conditions, you'll find that plants do well without any substrate nutrients sources.

You can ever cut the roots off and compare that against a control.
The plants had the same relative growth rates(RGR).

You are not going to beat microalgae through nutrient limitation in FW, to some degree PO4 can be used to limit some marine microalgae, namely diatoms.

When growing plants/macro algae, focus of their needs and the noxious microalgae will not grow.

Adding nutients to the substrate is simple, but the probelm is there is no way to know when the nutrients have run out.
Afterwhile, all methods end up relying on the water column.

All macro algae rely of the water column.
Microalgae need so little PO4/N etc that the leeching of these nutrients from the plants/macro algae will never limit them. Nutrients added to the substrate will be translocated upward into the leaves and be leeched out into the water column.

So that method does not work well for algae control.

Rather, focusing on thew plant's/macro algae's needs will help improve their growth.

This makes, sense since nice macro/plant growth was the orginal goal to begin with.

Give them what they want.
Let me know how the plants respond to the aeration.
You should see a decrease in microalgae on the glass and increase growth rates.

If curious, try turning off the aeration for 1- 2 days and note the change.



Regards,
Tom Barr


3rd annual Plant Fest July 8-14th 2005!
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[Samala]

Are you trying H. capensis? The grass does just fine at 68F.. I collected them at the tail end of the winter season on the IRL with water at 64F. I have no idea what the upper limit is likely to be with grass.. I know I've been snorkeling in turtlegrass and manatee grass beds that felt like bathwater, and the FL Keys can get up to 78F or more in the high summer periods at surface temperature.

So, to answer, yes, I think 68F is completely fine. Lower than 60F and I might be tempted to try eelgrass, which is the northern, temperate version of East Coast seagrasses.

>Sarah

[Plantbrain]

I'd really like to see some Penicillius in that aquascape.
Consider doing a nice arrangement with these plants.
Look for nice rock with lots of character and consider looking into asian rock design.

SW plant tanks are rare and doign a nice aquascape will speak volumes vs simply a jungle or a plain tank.

A picture is worth and thousand words and speaks in every language.

Put some ffort into it after you get a feel for things and always make sure you have high plant density.

When you have high density, this means the tank needs more nutrients to keep the weeds growing. So you will need to add things like KNO3, etc.

Fish waste alone cannot support the plant's needs nor is it balanced.

On a large tank, a small refuguim works well, but if you increased the size, then you'd have to have far too many fish in a small glass box and a build up of NH4 will cause all sorts of havoc.

NH4 is candy for algae spores(FW or SW). NH4 is mainly NH3(the much more toxic form) at marine pH's so things are more troublesome there as well. The relative NH3:NH4+ concentrations are pH dependent. In most FW systesm they are slanted towards the less toxic NH4+.

That, more than NO3 from an inorganic source, is the problem. Bacteria will convert the NH4 to NO3, but there is an O2 drain for that, and also plants/macro algae will suck it up quickly before the bacteria ever have a chance.

Then you have denitrifyers going after your NO3.

Regards,
Tom Barr

[Fredfish]

Thanks for the answers guys.

Sarah. Havn't gotten back to the flow dispersal device yet. I have been working on lighting and substrait for the refugium tank. Once the dust settles, I will start up flow between the two tanks again and play. I havn't forgotten you and I will post pics eventually.

Tom, you wrote "Microalgae need so little PO4/N etc that the leeching of these nutrients from the plants/macro algae will never limit them"

If micro algae cannot be po4 or N limited, what is the limiting nutrient when macros out-compete them?

In my fresh water days, I grew all my plants with a little potting soil in the substrait. Worked very well for me, but as you point out, these were all plants that grew emersed for part of the year.

So, if seagrasses get the majority of their nutrients from the water column, I should not have to worry about enriching the substrait? This seems to contradict other advice I have received here. I seem to remember you suggesting that Thalassia (sp?) would benefit from or needed (can't remember which) a deep enriched substrait. Am I missing something?

Fred.

[Plantbrain]

If micro algae cannot be po4 or N limited, what is the limiting nutrient when macros out-compete them?


There is none other than perhaps NH4.
There is not competition really, micro algae are in a completely diffetent niche than macro algae.

Uptake dynamics, Surface area ratios, transport, growth and mainteance requirements, many differences, even though they both are autotrophs and can use the same nutrients.

Would you consider a mice and elephants in the same niche?
Both are herbivores. One lives a very long time and one does not.


In my fresh water days, I grew all my plants with a little potting soil in the substrait. Worked very well for me, but as you point out, these were all plants that grew emersed for part of the year.


Well, the plants will grow better if you added nutrients to the water column. Most folks were ascared of PO4 in FWE planted tanks. Soil works as a nutrient source in a non CO2 enriched tank for about a year or less.

Then you must rely on the water column or tear down and add fresh soil.

Another trick: add water and soil and make mud ice cubes.
Push these down into the gravel.

You cannot easily test substrate nutrient lebvels so you don't know when they run out or not. If the soil gets into the water column= big mess, or leeches NH4 => algae.


So, if seagrasses get the majority of their nutrients from the water column, I should not have to worry about enriching the substrait? This seems to contradict other advice I have received here. I seem to remember you suggesting that Thalassia (sp?) would benefit from or needed (can't remember which) a deep enriched substrait. Am I missing something?

Fred.


Main thing with the sub for marine systems:
Add some organic matter, mulm/detritus from an established (vacuume the substrate good)tank. Or add a little soil or peat or leonardite, any organic matter. The Carbon will give the bacteria something to eat, bacteria need their carbs and limiting carbon in a new tank set up causes new tank problems very often.

Adding the mulm is the best thing.
I like Onyx sand for Marine plant tanks, Grey coast calcite is the exact same thing. Aragonite and some mulm/detritus works swell though.

This is all that's behind Miracle Mud. No miracle at all if folks had asked me:-)

I do suggest 4-5" deep substrates, more is better.
All I add is mulm to a new tank.
If you want, you can add more richer things such as soil.

A trick for soil to prevent NH4 issues: soak the soil for 2-3 weeks ina shallow tray to oxidize/bacterial conversion of the NH4 to NO3, or you can boil the soil also(oxidizes it into NO3) for 10 minutes.

I think many folks simply do not have the experience and background I do when it comes to larger plants/macro algae so my advice has traditionally been different.

It's my job, academic background, passion, research etc. Few Marine folks take biogeochemistry of aquatic soils/sediments.

Folks now add PO4 and know how to knock out every species of algae in a FW planted tank. I've been able to do a lot of algae control issues for folks in the Marine hobby as well and speak at marine societies as well as FW planted talks.

I also construct and contract out large marine or FW planted tanks as a business and have several clients, as well as lake management for clients. And of course, you can come ID and collect close to 50 species of Marine plants in the Keys this July.

Nothing like seeing plants in nature where you are in the tank instead of peering into one, think outside the little glass box.

Regards,
Tom Barr

3rd annual Plant Fest July 8-14th 2005!
subscribe@BarrReport.com Get connected
www.BarrReport.com Get the information

[Samala]

Plantbrain says
I'd really like to see some Penicillius in that aquascape.
Consider doing a nice arrangement with these plants.
Look for nice rock with lots of character and consider looking into asian rock design. SW plant tanks are rare and doign a nice aquascape will speak volumes vs simply a jungle or a plain tank.

Absolutely. Its been such fun just seeing some things work that I haven't had time for much artistic... um.. expression with the aquascape. ;) Now that I know approximate growing habits, rates and such, I can start planning something really cool. I'm considering some of the calcified macros, and some of the tuft-like macro's in the Chaetomorpha genus for variation in leaf shape and height.

I'm not sure what kinds of rock will be appropriate for a biotope approach.. but that was something I wanted to integrate eventually. There is another member here - Triterium - planning a very large seagrass tank that has the coolest grotto effect with some rock in his tank. I guess I'll have to 'punish' myself and do some snorkeling in the grass beds this summer to get some ideas. :p

NH4 is candy for algae spores.. In most FW systesm they are slanted towards the less toxic NH4+.

Dont I know it! I miss my Apisto blackwater tanks where algae was never an issue because the water was sooo acidic very little NH3 ever evolved. Course, the plants weren't big fans of that water either..

An observation I wanted to share, echoing Tom's words on root development.. some of my manatee grass is growing really well, but comes out of the sand quite easily. Very little root development on them. I'm not sure if that's because I'm making life easy on them with water column supplementation or there is something more behind it. But, it fits the pattern.

Oh yes, biogeochemistry of aquatic soils doesn't sound like a lot of fun.... biochem was enough for me. Adding another prefix can't be good. I hope I dont have to take that. ;)

>Sarah

[Samala]

Hmm.. well five days into mega aeration via skimmer and I have no skimmate to speak of and some nice lookin grass. It has definitely grown faster this week and there are a few new plantlets poking up out of the ground. I also didnt have to dose bicarb the last two days because Alk held stable overnight. I imagine this indicates the plants have effectively switched back to CO2 over bicarb molecules as a C source?

However.... this has triggered a small brown diatom-looking bloom in the tank. Its not choking the grass or anything on such a scale but small patches of it are showing up on the glass. Perhaps I need to rethink my dosing schedule as faster growth = faster consumption of N and P. What do we think?

One more thing - an article I found on stargrass suggests that they prefer glutamic acid to potassium nitrate as an N source. (??) Maybe this is why my B vitamin mix had an impact, I think there is some in that formula.

PS: I'm in a terrible mood.. anyone who thinks science isnt cut throat should shadow me. We got scooped by another lab that published in Science this week...... :( There is however a cool little article on zooplankton in the same issue. (See how I can seque between marine hobby and the real world? :D)

>Sarah

[Triterium]

Great information on this thread, thanks Tom and Sarah!

Sarah, that tank is looking great. I finally got my seagrasses in and they are beginning to grow, woohoo :D

[Plantbrain]

Originally posted by Samala
Hmm.. well five days into mega aeration via skimmer and I have no skimmate to speak of and some nice lookin grass. It has definitely grown faster this week and there are a few new plantlets poking up out of the ground. I also didnt have to dose bicarb the last two days because Alk held stable overnight. I imagine this indicates the plants have effectively switched back to CO2 over bicarb molecules as a C source?
[quote]

Ahh, you learned a valuable, yet very simple and easy lesson.
Plant biomass is mainly Carbon.

The focus should be on the plant's needs.
Your conclusion is correct and the diatom issue is also.

[quote]However.... this has triggered a small brown diatom-looking bloom in the tank. Its not choking the grass or anything on such a scale but small patches of it are showing up on the glass. Perhaps I need to rethink my dosing schedule as faster growth = faster consumption of N and P. What do we think?


The diatom bloom should be temporary.
Only attacks the glass.
As PO4 declines more, the diatoms should back off.
I don't mind some soft glass algae once a week, but it can become annoying.

Not sure about the limits and constraints of the diatoms just yet.
I know I can add PO4 and induce them.
I also know they come mainly in the start up phase but unless you add PO4 or neglect the tank, they are not an issue.

I have the answer for you on the plants, why the diatoms?
algae prefer CO2 as well.

Changes in the CO2/NH4 content let the algae "know" => sets off a series of inducible genes in a spore/cell to grow.

When CO2 goes up and NH4 goes down, that means no one else is around these are good environmental signals(like rain in the desert, warmer weather, longer sun light day lengths etc).

Thus a good time to grow if they can get a good jump on the competition.

CO2 and high light can also drive photorespiration and many algae have a rough time with this, plants are not as impacted, but their growth rates can be reduced by this process.



One more thing - an article I found on stargrass suggests that they prefer glutamic acid to potassium nitrate as an N source. (??) Maybe this is why my B vitamin mix had an impact, I think there is some in that formula.


Perhaps you mean glutamine?
NH4=> via GS/GoGat=> Glutamine
NO3 needs 8 electrons to be reduced to NH4.
While plants perfer NH4 over NO3(in general), so do micro algae.

This NH4 means a lot more to a little single celled algal spore vs a huge billion celled weed that has plenty of N reserves for NO3 transporters. Basically the plant has the activation energy required to use NO3, wereas an algae spore does not.

Also, the NH4/will be far more toxic and GA may degrade into NH4/NH3, you can add the relatively benign NO3 without much issue, NH4 is playing with fire.

I suppose other forms, and you can also chelate NH4 as well, but then you lose some of the efficacy that you are trying to provide the weed with in reduced energy.

Plants, all of them and algae leave the ETDA, Gluconate etc out side and need to remove it from the chelator prior to bring it into the cell.

The stronger the bond/complex, the less the plant gains with a more preferred form.

There are trade offs.


PS: I'm in a terrible mood.. anyone who thinks science isnt cut throat should shadow me. We got scooped by another lab that published in Science this week...... :( There is however a cool little article on zooplankton in the same issue. (See how I can seque between marine hobby and the real world? :D)

>Sarah

Sorry.

Does not degrade the research you have done. Only confirms it.
Many of the things I deal with transcend the hobby and into my field and vice versus.

I kill and grow weeds(yes, I get paid very well to grow plants), I have more funding than I know what to do with. If I have independent confirmation, super. Simply means I don't have to answer that question, on to the next question........look at the positive side....

Don't get down, you are the golden goose..........cook up something new.

A dozen more questions arise anytime a new piece of research is done. I'd look there for any good scraps.

Also, get good at pilot test. They are guesses, but don't dismiss nutty ideas either. They are often the ones you do not expect to work but often do. Quite humbling.

Regards,
Tom Barr

[Samala]

"Inducible genes".. now we're talking my language! ;) Thanks for the thoughts.. the points on NH4 accessibility is especially well taken. I'll be screening that vitamin solution from now on for this kind of fall out.. probably just cut it from the list for a while to see an effect on the tank. Thoughts on diatoms are great, quite logical, I feel I should have realized them myself.

Oh and thanks for the encouragement on research. You're right, more questions, that's the game. Still, as I hear, 'publish or perish'. :p Thanks again Tom!

>Sarah

[Plantbrain]

NH4 transportors are poorly understood, but it's my understanding with the transportors that have been studied, that NH4 is not inducible(constitutive-eg always produced whether or not the substrate, NH4 is present), wereas NO3 generally is and is much more understood, likely because you can inhibit it by adding NH4.

Plants are lazy like us, a free meal is always welcomed, if there is a little NO3 (say 1-2ppm of NO3) and not much NH4 around, then they will induce one NO3 high affinity transporter.

If there is a stable high level of NO3 (say 15ppm) and not much NH4, then the weed will induce a low affinity transporter.

Some plants have dual functions on the same NO3 transporter even. That's pretty cool.

So the NH4 will be removed at a fairly steady rate first, then when it gets pretty low, NO3 transport begins.........if you maintain a stable level of NO3, then the plants will continue to use the enzyme transporter.

Now if you add pulses of NH4(messing in the tank, poor environmental conditions, neglect, uprooting, cleaning filter etc) then you freak the plant out.

When the NH4 is present, often times the plants will inhibit the NO3 and sometimes chew those enzymes up.

So if NH4 is kept to a minimum, NO3 maintained at a stable level(which keeps the NO3 inducible transportors going at full blast), then you have the best growth without noxious algae.
Some transition peroid is required but after a week or two, things should settle down and get going well.

Micro algae can respond very quickly, a big billions celled plant does not. Micro algae have a much higher surface to area S/A ratio so they are better at less, plants can take up larger amounts.

Think about a mouse and an elephant for a comparison.
Both are herbivores. One reproduces fast, the other slow, but has a much bigger belly and ain't something you keep in your home. You need more food and room for it. Mice do not live long, elephants as long as us. Plants and microalgae are very similar tot his comparison.

Publishing (volume is the main thing) : get as many papers as you can. Even little ones etc, side projects, collaborations, get your name attached, work together with other folks to do this. Ask Bubba to help with the GIS, or Protein columns while you do the stats, general overview/writing, grant submissions or what have you.

Heck, if was just one person, it'd take forever.
Smaller chunks, answer issues important to what the grant committees want.

Teams work well for this reason.
Science, business, sales, this hobby etc, it's still all about people and helping others.

Regards,
Tom Barr