Mangrove Experiment - 50 Gallon tank

[RawFish]

I'm positive that if I leave the tank with no mangroves, the levels will get back to what it was before: Nitrates at 20ppm every 2 weeks. My next move will be to match the recommended ratio Mangrove/Gallon (1:10) and watch my dreadful nitrates disappear.

How fast you think it will take?

[davy182]

3 days I think, maybe we should do a pool.

[SimilanRocks]

I'm interested to see the result. I'd think you need 1:2 for tank+sump volume. That's about what eddybabyhd is using.

I tried 1:10 with MA before didn't see much different.

[m2434]

Originally posted by eddybabyhd
I think on a small scale it is almost inpossible to accuratly measure the benefits. Thats kind of why I took mine to the level I did. No one can convice me that my mangroves do not provide benefit.

Although I am open to discussion

Any plant or algae should consume nitrates, so I'm fairly sure there would be a benefit. Again, it's more just a question of the practicality of it. Seeing a real difference on a small scale would at least hint at this... The difference RawFish is seeing very well may be real, but it is tough to say for sure, there are a lot of factors, know and unknown, that can't be ruled out.

[capn_hylinur]

I am still lurking ---I've bought everything but the mangroves

There has been some talk on another thread that having two fuges a mangrove and a chaeto can actually deplete the nitrates and phosphates to a point where the chaeto and the mangroves die off
any opinions on this?

[eddybabyhd]

i could vouch for that, In fact, to the point where the other types of macro die first...Never had the cheato or mangroves, but the different types of caluerpa have died off, all thats left is the other two

[bertoni]

Caulerpa can outcompete Chaetomorpha for food in a wide variety of setups. It might be able to do the same to mangroves.

[Randy Holmes-Farley]

Such comparisons are very prone to differences in lighting, perhaps chemistry (iron), etc. The exact species/strains of Caulerpa, mangroves, and chaeto may also be important

In my refugia, where chaeto and Caulerpa racemosa were in together, and I dosed iron, the Caulerpa won out.

[capn_hylinur]

Originally posted by Randy Holmes-Farley
Such comparisons are very prone to differences in lighting, perhaps chemistry (iron), etc. The exact species/strains of Caulerpa, mangroves, and chaeto may also be important

In my refugia, where chaeto and Caulerpa racemosa were in together, and I dosed iron, the Caulerpa won out.

Did you run your refugium along with a protein skimmer. I questioning if you go the route of refugium(s) whether you need the protein skimmer--or that the ps can outstrip the dissolved organics that the macro algae and mangroves need?

[Randy Holmes-Farley]

I do not believe that algae or mangroves use organics. Such autotrophic organisms are generally believed to be sources rather than sinks for organics.

That said, I skim.

[greenbean36191]

Any plant or algae should consume nitrates, so I'm fairly sure there would be a benefit. Again, it's more just a question of the practicality of it.

Exactly. The question of whether plants take up N and P was settled a long time ago. The real question that needs to be answered is what are the rates of N and P uptake by small mangroves vs. macroalgae when you standardize both methods by biomass, volume, and cost. I strongly suspect that macroalgae wins in every category.

I imagine the idea for mangrove filters originally came from someone who heard that mangrove forests were being destroyed and reefs were dying as a result. The problem there though is the resulting siltation, not nutrients, and generally we don't have siltation problems in the hobby. The pattern of mangrove> seagrass> reef along with the patterns in primary productivity and N/P uptake along that gradient suggest that mangroves are mostly functioning as mechanical filters because their gnarled roots slow the water and allow the solids to settle and most of the nutrient reduction is happening in the seagrass.

You can certainly load up a 10 gallon tank with a dozen mangroves and stick a $50 light over it and you should see a reduction in nutrients, but why would you do that if you find out you can get the same result from a handful of Chaetomorpha under a $2 fluorescent?

[eddybabyhd]

you can grow mangroves under the same compact fluorescent lights, I have done it

[RawFish]

I chose mangroves because I don't have a sump or fuge, so I can hang them in a plastic container, in the back of the tank.
I had a nice red macro-algae... but tang ate it! Pretty soon that yellow guy's gonna start eating the live-rock! But that's another thread: Yellow Tang Ate my Tank!

[capn_hylinur]

Originally posted by Randy Holmes-Farley
I do not believe that algae or mangroves use organics. Such autotrophic organisms are generally believed to be sources rather than sinks for organics.

That said, I skim.

thanks Randy--I see the concept difference here.

Sorry I meant phosphates and nitrates not other organics.

So my question is:

Will two refugiums--for mangroves and chaeto--actually outstrip the phophates and nitrates in the total water column and die off eventually(somewhat like in the case of an algae bloom)

[capn_hylinur]

Originally posted by greenbean36191
Exactly. The question of whether plants take up N and P was settled a long time ago. The real question that needs to be answered is what are the rates of N and P uptake by small mangroves vs. macroalgae when you standardize both methods by biomass, volume, and cost. I strongly suspect that macroalgae wins in every category.

I imagine the idea for mangrove filters originally came from someone who heard that mangrove forests were being destroyed and reefs were dying as a result. The problem there though is the resulting siltation, not nutrients, and generally we don't have siltation problems in the hobby. The pattern of mangrove> seagrass> reef along with the patterns in primary productivity and N/P uptake along that gradient suggest that mangroves are mostly functioning as mechanical filters because their gnarled roots slow the water and allow the solids to settle and most of the nutrient reduction is happening in the seagrass.

You can certainly load up a 10 gallon tank with a dozen mangroves and stick a $50 light over it and you should see a reduction in nutrients, but why would you do that if you find out you can get the same result from a handful of Chaetomorpha under a $2 fluorescent?

Thanks greenbean--as always very informative


I am still having trouble pin pointing my original question however

Is it possible through use of a refugium to outstrip the nitrates and phosphates in the water column so eventually the cheato or mangroves die off---somewhat like in an algae bloom when the tank is first cycling.

I guess I am trying to figure out what the long term effects of running a refugium are---I've have only had one running for 10 months now.
I have already discovered that there comes a point when you can't run the light 24/7. I started getting a build up of cyano in the chaeto--thanks to Sk8R two days with the lights off cured that

[greenbean36191]

you can grow mangroves under the same compact fluorescent lights, I have done it

I'm not saying you can't. It was a hypothetical supposing that you found out you needed more space and higher lighting to get growth and uptake rates comparable to macroalgae (which is very likely to be true). In that case running mangroves as opposed to macroalgae for nutrient export doesn't make much sense.

Is it possible through use of a refugium to outstrip the nitrates and phosphates in the water column so eventually the cheato or mangroves die off

Yes.

[Billybeau1]

Hey gb. good to see you visit the chem forum.

BTW - love the web site of you know who.

[H.a.Z]

eddybabyhd, your refugium is nicer than many tanks :-)

[Randy Holmes-Farley]

Will two refugiums--for mangroves and chaeto--actually outstrip the phophates and nitrates in the total water column and die off eventually(somewhat like in the case of an algae bloom)

To some considerable extent, refugia grow faster or slower in response to nutrients. A refugium of a single species will likely adjust its growth based on many considerations (light, nutrients, etc), but if and when nutrients become limiting, growth will just slow until it balances out.

Having multiple species in one or more refugia might get to the point where one can get enough nutrients to grow rapidly while the other cannot, and it is possible that one species might be out competed in that case. That happened to me with Chaeto and Caulerpa, leaving Caulerpa racemosa going strong. That exact outcome may not happen in all tanks, where other things may be different which might impact the outcome.

[capn_hylinur]

Thanks greenbean and Randy for answering my question.
I was about to add another refugium with with mangroves but I guess it is just over kill with the cheato refugium and skimmer I have.---good more money for corals and fish

[capn_hylinur]

Originally posted by Billybeau1
Hey gb. good to see you visit the chem forum.

BTW - love the web site of you know who.

yeah me too---I posted the link to the site not realizing the adult content to it--so it got nuked by the moderators---which is a good thing