Iron (Fe) dosing - how much/ how often?

[The_Nexis_One]

I know this is still an experimental topic and some people are not on board completely with the dosing of Iron at all....


However, my own personal experience with dosing iron has lead me to be completely on board and looking to learn more about how to use it to it's fullest.

So... as the title said - How much should I dose?

I have been dosing 1ml a day of Kent's Freshwater planted solution which isn't ideal because it contains a tiny bit of copper (0.00001% if memory serves) - but I haven't seen any negative effects and havent' been back to the LFS to pick up some SeaChem "Flourish Iron" (which is the only other source I've found locally).

So, back to the question - I can continue dosing 1ml every day and I'm sure things will be fine. However, while the growth is exceptional compared to the slow death my macro's were seeing previously - it's not steady, nor is it what I would expect. Most fronds are shorter than the parent colony (at LFS) and the growth appears to be more in the runners rather than dense fronds. If I increase the dose - what should I look for as warning signs? Is 2ml a day too much? or 3ml? (system is ~75gal as it stands right now)

If I increase the dose to 'some amount' a day and don't get a reaction, should I continue to increase until I "do" see a reaction (positive or negative)?

...or should i just be happy with my growth and leave it alone...

I'm hoping to get this all worked out and tested before I spend some money/trade for a pile of beautiful Macro's and some salty plants to finish up the lagoon tank. :-) I like to have all my homework done before it comes time for the test

Many Thanks,
John.

[Samala]

Hmm. All good questions (as usual!), you're making the gears in my head smoke.

You pointed out that a lot of your growth is in the runners and not so much in the fronds, that's very interesting. I have this kind of 'leggy' growth in the really high light tanks (pushing 10+wpg). It may or may not be related to light, same for nutrients. The high light tanks are also a wee neglected on nitrate dosing (they should really be put on a drip doser) so that could be a signal of low N, or low P, or something else even I suppose. The fact that they're growing at all is great I'd think!

I dose about 3drops per day into ~15 gallons (after displacement), but like so many other things in marine aquaria, uptake rates are going to vary so dramatically I'm not sure its wise to scale up from that 3drops/15gallons to 15drops for 75gal. If you're adding too much each day, and not having it removed (uptake + water changes filtering it down) then of course you run into overdosed environment.

I have yet to find a warning signal for too much Fe, though, thinking about it, a big diatom bloom might be OD'd Fe related, they are the dominant micro during Fe supplementation in some habitats. Low Fe is a hairline qualitative signal too, the Caulerpa's slow in growth and get a little paler in color (though this can also mean low N so I check that first.)

As before, when I dose I shoot for the lowest possible reading on a decent kit.. I think thats 0.05 ppm, but, as warned before, thats quite a bit above NSW values.

I think we just need so much more information than we have, namely a bioassay done to evaluate just how toxic Fe is at low levels and what the symptoms of overexposure are. You might be able to con it out of Kent or Seachem's R&D teams, but they might not release much information to you.

I was planning to warm up some Ilyanassa snails this week and give them a high protein diet to intiate a breeding cycle with them, then use the eggs/larvae in bioassays with exposure to various ppm thresholds of Fe in the water. Crude assay, but might be usable for our applications. Ilyanassa survives a lot of stuff that most inverts would perish under though, so along with that project I was hoping to do Xenia and one more.. perhaps grass shrimp or urchin if I cant get ahold of an urchin to use.

SO..... we're kinda back to square one. My biggest question is: how much light is over your tank? And what have you got to lose in inverts if you try to push the Fe dosing rates? I also wonder if you tried to push the dosing if you'd end up driving a precipitation event, or if it would render your rocks unusable (leaching?).

Hmmmmmm. Sorry I cant throw out more answers but maybe a little discussion is wise.

>Sarah

[The_Nexis_One]

Originally posted by Samala
Hmm. All good questions (as usual!), you're making the gears in my head smoke.

yes.... stretch those neurons!

You pointed out that a lot of your growth is in the runners and not so much in the fronds, that's very interesting. I have this kind of 'leggy' growth in the really high light tanks (pushing 10+wpg). It may or may not be related to light, same for nutrients. The high light tanks are also a wee neglected on nitrate dosing (they should really be put on a drip doser) so that could be a signal of low N, or low P, or something else even I suppose. The fact that they're growing at all is great I'd think!

yeah, runners with very short fronds, like .5" tall w/ runners pushing .75" a day in additional length. but yes - any growth is SUPER IMO.

I was planning to warm up some Ilyanassa snails this week and give them a high protein diet to intiate a breeding cycle with them, then use the eggs/larvae in bioassays with exposure to various ppm thresholds of Fe in the water. Crude assay, but might be usable for our applications. Ilyanassa survives a lot of stuff that most inverts would perish under though, so along with that project I was hoping to do Xenia and one more.. perhaps grass shrimp or urchin if I cant get ahold of an urchin to use.

That would be very cool... Please do let me know your results, even if they are crude. As for the urchin - I'd love to give you mine... the little bugger refuses to stop wearing my Macro's AS A HAT! Unfortunatly, most of the runners that come off the main colony rock get picked up, pulled off and swirelled around the Royal Urchin. Oddly - they are growing there.... guess that's one way to keep your macro's from gathering detritus . If you were closer - I'd bring the little guy by and thank you in person.

SO..... we're kinda back to square one. My biggest question is: how much light is over your tank? And what have you got to lose in inverts if you try to push the Fe dosing rates? I also wonder if you tried to push the dosing if you'd end up driving a precipitation event, or if it would render your rocks unusable (leaching?).

Well... let' see. The macro's are in the Lagoon with the Mangroves. The mangroves are on one side and macro's on the other. The macro side has a single LOA 65W CF with a 6 week old bulb (lasts 6 months normally without issue). The light is sitting on some foam blocks, which sit on the egg grate which covers the lagoon (because of the Snowflake). The light has the clear cover removed (found the ballasts last longer with better air flow) and the bulb is 6" above the water and 12" above the main Macro colony. Other small colonies are to the sides and some bits are growing elsewhere on the extremities of the lights projection.
As far as inverts. The system totals like this: I have ~6 snails, ~25 hermits, 1 Royal Urchin, 1 Kupang Damsel, 2 Green Chromis, 1 Snowflake (~23"), 1 Peppermint Shrimp, 1 Mithrax crab, 1 Tigertail cuke, a handful of small red starfish (reef-safe hitchhikers), a metric boatload of worms (spaghetti I think), a Rock anenome, a starter of Xenia (to see if it would grow), a starter of green star polyps, ~25 zoanthid polyps, 2 small patches of Bryarium (receeding since the large tank crashed). ....I think that's it (pathetic i know, but I gave away all my nice stuff since this was to be a temp setup to keep LR and fish alive until I buy a house.) Nothing super amazing, but the Eel has too much personality and the Kupang has been with me since the start, so I'm in the Moderatly risky section of the graph... just don't want to do anything that'll kill my bud's or destroy my LR investment

As for leeching...... I'd REALLY like to not kill my LR or poison it such that it can't be used when I setup the 157g again.... that being said, I don't think that Iron leeching would be a bad thing especially if something was using it.

Hmmmmmm. Sorry I cant throw out more answers but maybe a little discussion is wise.

No worries - I'd rather have someone to work through things with than someone pointing and blindly telling what is write and wrong from a thousand miles away -- anytime you wanna talk, I'll be more than happy to listen and try to sound intelligent

Many Thanks Sarah,
John.

[The_Nexis_One]

I stopped by the LFS on the way to a client and picked up some "Seachem Flourish Iron". I'm not preferential between EDTA or Gluconated iron sources (and this was all they had), so I'll give it a try.

I'm confused through about how to determine the dose... This product suggests 5ml/50g (Freshwater) will produce 0.10mg/L iron. The Guaranteed Analysis is:

Iron (Fe) ................. 1.0%
- - 1.0% Soluble Iron (Fe)
Derived from: Ferrous Gluconate


I will start out with .5ml and.... I guess I need to pick up an Iron test kit and stop flying blind... :-/ I know the kits are inaccurate and only indicate when you've gone too far (potential overdose), but... it's better than nothing - which is what I have now.



John.

[3D-Reef]

Well,if a diatom bloom is a sign of ODing on Fe,then I think I've found it.
Man that Sarah is a smart one,ain't She?
Currently, My tank has a bloom going on,but as far as I can tell nothing is going wrong.I'm going to back off of the 15ml/250gal per day to 7.5ml.And see what happens.
What I have noticed, is that the stag horn has darkened a little.But since then the Po4/cyno has gone andI'm seeing new growth now.
The Hydnophora,Tubastraea,montipora,sea whips,gorgonians,all look about the same.
Now what I didn't expect was that the Dendronephtya is staying out "happy"most of the day now.Possibly due to the diatom bloom? Who knows?
I looked for a Lemotte test kit,but to no avail,and the sea chem kit still won't read any Fe,even at these high levels.
Clay

[The_Nexis_One]

Thanks for the info 3D !

I came home from a quick stop at the LFS after work today with 5 Margareta snails, 10 more Hawaian Hermits, a Queen Conch, and a nice bag of free Feather Caulerpa from their rock curing bin.

... but no test kits... it doesn't sound like it would do me much good though... thats why your report of Diatoms is that much more important. I'm going to stick with 1ml of the Flourish Iron for a week or two and see how things respond.

Many thanks,
John.

[The_Nexis_One]

Update 03/08/06

I skipped dosing over a weekend while I as out of town. While growth continued in the Macros, it slowed and they were partially overtaken by Cyano/Micro's. I started dosing 1ml daily again Monday morning and now (Friday morning) the growth has returned to ~5 new fronds and ~3" of runners a day! The Cyano/Micro's have slowed and haven't proceeded off the fronds they killed (the original fronds of the starter I got and a few others). All new fronds since Tuesday are Cyano/Macro free.

I'm curious if the macro growth is removing the phosphate from the water such that Cyano growth is retarded. Then when Iron dosing stopped, the macro growth slowed and phosphates became available to the cyano again. It was very apperant that the cyano slowed to a stop rather than something like it grew while I was gone and stopped before I got back. I was watching it take over fronds as hours passed... (sunday night/Monday morning) until it started to slow after dosing iron and eventually completely stopped tuesday afternoon.

I have been dosing with the Iron bottle cap and I think I'm going to go back to the syringe. I have noticed that my rock anenome and sponge seem to react to my inaccurate dosing... if I dose daily a .75 or .8 ml amount I think this will be a much better middle of the road. I'm happy with the growth rates and the retardation of Cyano/micro's while dosing 1ml, but I'm concerned that it's more than I need.

Also, I have stopped dosing NO3 for the time being. I was dosing it daily as well, but after skipping the weekend, I noticed that it was still at ~5ppm The test kit is difficult for me to read and it seemed to not matter much as to how much i dosed... or didn't dose. I'll test this weekend while I do some work on the system and will report back how the NO3 looks after a week without dosing.

Lastly, the Mangroves are growing GREAT. The new propagule that had recently stalled root production and had produced it's first couple leaves is dropping large healthy base roots that will soon let me drop it to the sand bed. The mature mangrove is producing lots and lots of new leaves and the latest root is almost down to the sand bed (~6.5")

Time for a little experimentation testing

John.

[Samala]

Wonderful! I'm so glad you keep us updated John, I've asked everyone who wonders about nutrients to keep us posted and you are one of the few who has done such a nice job of updating logs and observations. Its really really valuable info.

I think your musing of, "Then when Iron dosing stopped, the macro growth slowed and phosphates became available to the cyano again.." is the right thinking for nutrient dynamics in closed systems. Especially true when nitrates are available and iron is limiting. Or.. if theres lots of 'lower' N products floating about that are algae candy.

PS: On Fe overdosing.. I got a diatom bloom yesterday after giving the tank Fe dosing. After a weekend away I figured the tank was probably low on Fe and added a weee bit more than usual (10drops more, the ones missed over the days missed) and, bingo, a few hours and I had diatoms. So I'm hoping this is still a relatively accurate way of judging too much Fe without a test kit.

Course.. major Fe overdose would probably be much more catastrophic.. like dead things. The bioassays on the snails will start this weekend, are you ready?

>Sarah

[The_Nexis_One]

Originally posted by Samala
PS: On Fe overdosing.. I got a diatom bloom yesterday after giving the tank Fe dosing. After a weekend away I figured the tank was probably low on Fe and added a weee bit more than usual (10drops more, the ones missed over the days missed) and, bingo, a few hours and I had diatoms. So I'm hoping this is still a relatively accurate way of judging too much Fe without a test kit.

Course.. major Fe overdose would probably be much more catastrophic.. like dead things. The bioassays on the snails will start this weekend, are you ready?

>Sarah

Right.... in review: Dead stuff bad, 'Diatom bloom' less bad, fat sassy macro's good.... ok, I think I got it

I've not had a diatom bloom, but I'm starting to get the feeling that my Rock anenome is my 'Canary'. This specimen was a rescue from a LFS who had several under poor lighting and had provided no direct feeding... so when I got it the poor thing was bleached white (one of those extra special *cough* 'white on white' variaties). It has since picked up a dominant chocolate brown colored Zooxanthellae and seems to be doing well.
On days I dose a bit more (using the cap method was very inconsistent so somedays in the previous week got 1.5ml, some .75ml, some 2ml) ... but my initial suspicion is that it appears that I am able to tell the Fe dose by watching the anenome a few hours later. On heavier dose days, it was retracted/shriveled within about 5-7 hours. Spending the rest of the day like that and coming back out to normal size by the next morning... Although come to think of it, it hadn't come back out to it's full size until the Monday after my KC trip... hrm.. I'm going to have to get this camera thing straightened out so I can take daily pix of it and tag it along with my dosing records (*cough*...the ones I need to start keeping, that is). Ok.. now i'm really starting to wonder about this anenome thing.

Only time will tell as I had added another light to the near by section of tank in the last week - while the anenome is not in it's direct path, it may be reacting to that change since both were coinciding. Let this be an example for all those who break their own rules and change more than one variable at a time when they are trying to experiment...

Also, the sponge may not be reacting, as much as it originally appeared, to the Fe dosing. I'm sure it wasn't the NO3 becuase my levels now are MUCH lower than they were when I started dosing the Fe. I think part of it's stress was due to me rearranging / cleaning my MJ1200's and it's catching a lot more flow than previously. However, the partial color change from Yellow to grey still has me baffled. Regardless - I'm still dosing Fe and it's come back, at least part way, to it's original fluffy, growing, self. I suspect that if it initially reacted to the Fe (if at all) it's over it's issue and growing again... still something to keep an eye on.

John.

[3D-Reef]

Well I cut back on dosing fe and havn't noticed much of a change.But I also pulled a lot macros and took them to the LFS.FWIW, since then, my nitrates have come up from 2.5 to 5ppm.
I also pulled some fish out and in order to do that I had to remove the rocks.Now when I looked at the bottom of the rocks.They have an orange tint to the underside right at the water/substrate line.
Maybe another indicator of Fe overdose?
Clay

[DaMan]

Have you tried Redseas FE test? It takes a half hour, but seems to be accurate to me. I am uncomfortable dosing any element without testing to see if it necessary. But, I do find my tanks consume quite a lot of Iron.

[The_Nexis_One]

Originally posted by 3D-Reef
...I had to remove the rocks.Now when I looked at the bottom of the rocks.They have an orange tint to the underside right at the water/substrate line.
Maybe another indicator of Fe overdose?
Clay

Odd... are you sure it's not just a bacterial colony from the sand bed? When I pulled the rocks from my Refug when I moved, the under side of the LR was very colorful: blues, greys, black, white, orange (spots and tunicate/sponge), Yellow encrusting sponge, etc.

It does seem odd though. I wonder what color Iron would leave if/when it precipitates.... could that be the color of the chelator or other agent in the Fe solution?

John.

[The_Nexis_One]

Originally posted by DaMan
Have you tried Redseas FE test?

No, haven't tried any testing due to Randy Holmes-Farely's comments that all hobbiest level test kits aren't capable of showing levels of NSW.

I think the standing rule of thumb is "if your test kits shows it - you over dosed"

IMHO,
John.

[3D-Reef]

No..it doesn't seam to be bacterial.It's more of a uniform color of the rock itself.The sponges/featherdusters are still there and look like normal.I just thought it odd that most of the rock was that way,and wanted to get some feedback.Now I don't see any other indicators, besides some diatoms,(ie. dead things)which is always good.
Clay

[estrange]

I wouldn't mind overdosing iron to detectable levels if I was dosing only chelated iron. I've been using Kent's iron and there are copper and other stuff in it. Is there a place where I can find pure chelated iron? I'll guinea pig myself and try it if I can find a source.

[Samala]

Sequestrene, sometimes available at farm supplies, is a 10% chelated iron source if you can find it. Gregwatson.com carries it, but its enough iron for you to mix up a big batch and the supply everyone in this forum I do believe.

>Sarah

[The_Nexis_One]

Originally posted by estrange
I wouldn't mind overdosing iron to detectable levels if I was dosing only chelated iron. I've been using Kent's iron and there are copper and other stuff in it. Is there a place where I can find pure chelated iron? I'll guinea pig myself and try it if I can find a source.

What Kent product are you using exactly?

I'm having good luck with Seachem's Flourish Iron - although, I have good growth, but I'm also seeing more Cyano than I was with Kent's. I'm now starting to wonder if it's a bioavailability issue. I might try switching back to chelated (Iron only product) with the same dosing regime and see if things perk up any more. I was actually starting to get frustrated about the Cyano as it's starting to overtake my Macro's again.

John.

[Samala]

John it might be because the Seachem is a gluconated form of iron (ummmm I think it is!) which might cause you to have breakdown products in the water column. If it actually falls out of solution as Fe2+ and a glucose molecule of some sort then that glucose may very well easily and quickly be broken down to ammonia or nitrite.. either of which your cyano will gobble up with glee. I know I keep mentioning it but its the only thing I know about cyano in planted tanks so far.. I can induce cyano in two ways: having zero nitrates, and giving the tank ammonia to play with (dosed as ammonium).

>Sarah

[The_Nexis_One]

Hi Sarah!

Yeah... that's the sort of logic I was following too (minus all the cool science stuff ) I'm going to go get some Chelated Iron and try that.

Thanks for bringing the Chemistry Lesson! looking forward to the next installment.

John

[The_Nexis_One]

It was recommended that I check out greggwatson.com as a source of Iron and Nitrate dosing compounds - once there, I realized I had looked at it before. It seemed like a good deal so I figured I'd put togethor an order of everything I might need and get it taken care of all at once. While I was putting togethor the order, I started to wonder about the Iron Chelate he's using/selling. I remember reading some of Randy's work in the past discussing the issues with Iron Chelate vs. Gluconated Iron. Anyone have experiance with Mr. Watsons Iron product in a marine system?

From Greggwatson.com:

Iron Chelate 10%

Iron Chelate Sequestrene 10% is currently in stock and is available in one-half pound quantities.

Mix 3.53 ounces to make 1 litre of concentrated Iron Supplement solution.

I'm concerned that I may end up right back where I am at with a bunch of Iron solution that doesn't seem to work well in SW (as the gluconated Fe I'm tried from Seachem.

I tried to look up the Iron Chelate Sequestrene and found three types of Sequestrene a 330, 153, and 138 Sequestrene.

From Becker Underwood:

Becker Underwood's Sequestrene chelated micronutrient formulations are important to plant health. Unlike non-chelated or weakly chelated irons, Sequestrene 330 and Sequestrene 138 are strong chelates that maintain and protect iron availability in a wide variety of problem soils. Plus, Sequestrene has the added flexibility for either foliar or soil applications. Sequestrene 330, a 10 percent fully chelated DTPA iron, performs best in slightly acid to slightly alkaline soils with a pH of up to 7.5.

Sequestrene 138, a 6 percent fully chelated EDDHA iron, is preferred in the most challenging soils that are alkaline and calcareous, including soils with a pH greater than 7.0. Sequestrene 138 provides the strongest chelate available for these difficult situations.

From bioWORLD:

Sequestrene#153;

# Also known as: Fe-EDDHA Replacement for FeNa-EDTA.
# Store at room temperature.
# Soluble in water.

High performance iron chelates for foliar and soil applications.
Iron is essential for the formation of chlorophyll, a vital component to ensure plant health. Since iron has low plant mobility, new growth in iron deficient plants often shows iron deficiency. In early stages, leaves have intervenial chlorosis where plant leaves are light green to yellow but the leaf veins remain green. In severe cases, leaves turn white and plants may die.
Sequestreneâ„¢ 330 is a strong chelate that maintains and protects iron availability in a wide variety of problem soils. Plus, Sequestreneâ„¢ has the added flexibility for either foliar or soil applications. Sequestreneâ„¢ 330, a 10 percent fully chelated DTPA iron, performs best in a slightly acid to slightly alkaline soils wit a pH of up to 7.5.

So... what does all this mean? well.. to tell you the truth - I'm not sure. I can make lots of assumptions and learn when I'm proven wrong - so.. here goes.

My take on that info is that 'if' the compound from GreggWatson is of the 153 or 138 flavor - it'll work in SW... but the 330 would work best in FW and may not work very well in FW. So.. any idea which Sequestrene he's using? or does it matter?

I'm not trying to get personal with Mr. Watsons business, nor do I want to exploit or cause problems for him - I just want to know if the stuff he's selling is the right stuff for my setup. He seems like a nice guy from his web page and I wish him luck in his endevours.

Regarding my current regeme, I've started using the Kent FW Planted solution again since it has Iron Chelate. I'm dosing 0.8ml a day while I'm looking for a better solution to use. The day I started dosing it I noticed a pretty hefty growth beginning in my macro's The feather Caulerpa which had been transplanted showed ~5 white nodules on the existing fronds... by the next morning, I could see that they were all 1/3" long fronds growing off the original fronds and there were an additional ~8 white nodules elsewhere on the runner and old fronds. At this point (4 days later) I have doubled my frond count on the feather caulerpa in addition to another 3" of runner growth and the grape caulerpa runner has grown ~5" and produced another 6 new fronds (stem with grapes). Additionally my mystery macro popped a runner out of the sand 2" away from the rock it has taken hold on - I didn't think it was growing since I manually 'cleared' the rock back to about 10% of the original due to the cyano growth from the time when I was dosing the Gluconated Iron.

Moreover, I've partially ruled out Nitrate limitation from this issue becuase for the first 3/4 of the time I was dosing Gluc. Fe, I was also dosing KNO3 daily. However, uptake of the NO3 slowed to the point that my NO3 was rising well past 5ppm. I stopped dosing NO3 with the intention of resuming when it came back down below 5ppm and planned to continue testing weekly. At the end of that week, I installed a 12gal Rock Box plumbed inline with the lagoon drain and rebuilt the lagoon. I removed half the LR from both the display and lagoon and 100% from the Overflow refug. Additionally, I installed the Eel run under the DSB and deepened the DSB to 5-6" (shallowing the water another 1-1.5" throughout. The morning following the rebuild I tested the NO3 to see if the disturbance had produced any increase yet from the ammonia the must have been created. I found the NO3 to be zero and was suddenly concerned that the caulerpa would sporalate before the NO3 spike came through the "N" cycle. I switched back to dosing Chelated Iron 0.8ml a day due to the previous slow growth and Cyano increase and I dosed 3ppm of NO3 over the course of the day/evening. The next afternoon, I tested again and found the NO3 to be at 10ppm, I assumed the spike had arrived. Since then it's been a growth explosion in the macro's and Cyano has been mostly retarded again with limited growth on old caulerpa fronds.

Sheesh - sorry I talk so much LOL....

So does anyone have experiance/technical advice about using the Iron Chelate from Gregg Watson in a marine system?

Thanks,
John.