Phosphate using plants?

[modemfox]

I have had my aquarium set up about a year now and my deap sand bed finally started working. So as a result i have zero nitrates but i have phosphate reading of 1. So now my question is should i use a specific plant or macro to remove the phosphates? My refuge has every species of caulerpa and cheato with room to spare. I am planning to get some sea grasses but was wondering if the plants would use phosphates like some freshwater plants.

Please help, trying to get self maintaining system.

And for the record I use RO/DI water so phosphates have probably been building up from foods. I do water changes every week but it only drops them by half. I also feed very lightly.

 

[ozadars]

I believe sea grasses absorb phosphate from the sand with their roots so you need to dig them into your main tank, not refugium.

 

[Seahorsewisprer]

Look for a thread called "using no3 to reduce po4" or something to that effect....

 

[Samala]

Seagrass and macroalgae, will scavange phosphate from the system through their roots and their leaves. Leaves mainly for macroalgae (no true roots!). BUT, they need a nitrogen source in order to do it. From my experiments and nutrient charting.. it looks like seagrass and macroalgae need about 16 nitrogen's for every 1 phosphate they'll take up. In a tank like yours, with nitrogen already at zero (zero nitrate reading), the plants may not actually grow very much or very fast. Little or no growth means that they wont be able to help out your phosphate situation very much.

So- you have one of two options - go with the expensive phosphate absorbers like many reefers will suggest. But that will thwart your attempts for a self sustaining system.

Second option is to, get the grass and macro algae, see how they play into your phosphate levels, and possibly end up adding in a nitrogen source long term to get your phosphate levels to drop. It sounds crazy but there is some evidence for this already. More and more everyday really.

Check out that thread Aero mentioned and let us know what you think.. Your DSB is a perfect environment for seagrass imo.

>Sarah

 

[modemfox]

What do i add to get nitrates?

 

[modemfox]

Let me rephrase that! How do i add nitrates and not more phosphates at the same time?

 

[Seahorsewisprer]

I use Kents Botanicals Nitro+. It is made for FW. It is a nitrogen compund of nitrogen and sodium. Some use Potassium nitrate that is much cheaper. It is actually bought at the garden shop and used as a stump remover! Search "stump" and I bet it comes up...

 

[Samala]

Seachem also makes a product aimed at freshwater called Fluorish Nitrogen.. that has been working well for me.

But first get the tank setup and the macro going and see how your phosphate levels respond. You may not need to add nitrogen or may need to add only a little amount to keep the phosphate levels in check. Everyone's tank will be different based on water changes, skimming, feeding regime, amount and quality/efficiency of their LR/DSB/LS, water source, etc. So its hard to give you a hard and fast answer.

>Sarah

 

[modemfox]

You would think more research would have been done in this kind of setup by now. Maybe i am just trying to be leading edge.

 

[Samala]

It is a bit leading edge.. if its been done successfully for some time no one has stopped in to say so just yet. It was kind of an all-of-a-sudden thing too. I started wondering about it myself, saw some posts here and there hinting about it.. that phosphate thread came up (which is an awesome thread).. and then I heard Coral Magazine suggested nitrogen limitation in our tanks an issue back or so. All in the first half of this year really. So.. you get to be another proud owner of one of the guinea pig tanks. We're always glad to have another tank to add to the list of.. 'yes it does work, we're not really crazy'..

If you were interested instead in exactly how plants and macroalgae uptake phosphate and nitrogen specifically I could probably email you some papers on it. Scientific nerdy papers that is.

>Sarah

 

[Fredfish]

Yup, definately leading edge. I recently started dosing nitrogen in my tank since it hit undetectable levels. I've let the nitrogen bounce up and down a few times and I notice a diference in the macro. Once the nitrogen drops below a certain level the macro starts to get pale and individual blades start to turn transparent.

As soon as I dose the algae greens up again.

we're not really crazy'..

Speak for yourself, I'm certifiable.

Fred

 

[Seahorsewisprer]

It might take a while for this "crazy talk" to catch on. The articles in Coral Magazine this spring (it was actually a series) was written by Jorg Kokott, the guy who proposed addind Vodka to our tanks and who inspired Borneman to write a very interesting editorial.

The series also mentions the importance of Fe (iron). Since I've been testing and adding No3 and Fe, I have not noticed a testable decrease in Po4, but I did just redo my planted tank, and removed a lot of macro. The new "frags" I got are starting to take off, though!

My nuisance algae seems to be decreasing. And, the cyano is gone every morning, comes back a tiny bit during the day, then is gone again!

(My hair algae isn't as pretty as Triteriums)

 

[geoff72]

You can always try Mangroves. Some sites say they are really good at removing Phosphates. You never know. Do a search on them and you will see both oppinions.

 

[Seahorsewisprer]

There is an interesting article in RK mag a few months back....I think they grow too slow to actually do much good...I like mine, though. I think they are cool house plants!

I even put some in my main display!

 

[Plantbrain]

Well, it's been a few weeks, but you all have learned the Crazy plant talk and have realized what I've been saying for many years.

Glad to finally see folks adding NO3 and watching the macro algae response to NP and Ca/Alk.

I'll tell you this: most of the knowledge you will gain from your own on this topic, not companies.

They follow us on this.

When I suggested to folks at Marine Aquarium societies about this and on line, few listened initially, but I think there is enough critical numbers of folks on line to realize the confirmation that I've known for many years does apply.

As more try it, they too will realize the planted dynamic, it's not quite the same as Freshwater, but.........it does apply in many cases.

I think approaching it to others from this view point:

"Don't argue that it does not work etc, because when I add it my macros grow better/faster and I have less nuisance algae.

If what you say is trrue, that adding it will causes issues, then where is/are my problem/s? The test kits(Lamott, lab spects etc) confirm the uptake(DBS are not resposible for PO4 removal etc).

Don't believe me, try it for yourself and then you'll know,........"

Any new dosing is a leap of faith, as more folks report success, more will follow "the herd" as it were.

You need to realize that when applying this approach, the other things cannot be limiting, such as Ca, Alk, temp variations etc low aeration, low density/surface area of plant biomass etc, herbivores that eat the plants etc.

Be careful there, folks overlook many things.

I'll be doing a series of marine macro algae test at UC Davis shortly, namely on the invasive weed C taxifolia. They need someone that knows how to grow it well in culture and I do not think they could have picked a better person if I do so say myself haha

Unlike the Europeans, we killed it asap here in CA.
Rapid response plans for weeds do work well. Slow bickering only allows the weed time to establish firmly.

Cost less to treat, does less damage, better environmental damage, less permenant program cost as projects grow and ebb as the weeds are eradicated.

Would you like to pick an infested tank full of Byropsis or only 1 or 2 tufts?

Same thing applies in nature.'

Regards,
Tom Barr


ww.BarrReport.com

 

[Fredfish]

Hi Tom. Welcome back, we missed you.

You need to realize that when applying this approach, the other things cannot be limiting, such as Ca, Alk, temp variations etc low aeration, low density/surface area of plant biomass etc, herbivores that eat the plants etc.

Yup, thats where I am at now. I can keep my macro from going sexual by dosing nitrates, but its not really growing fast at all.

I need to work through critical parameters to figure out what is limiting growth.

On a related issue, I have been looking at trace supplements for the tank. I happen to have a two part Guillard's f2 that I have been using for phyto. If it grows good phyto, should the micro nutrient portion not be good for macros as well?

Fred

 

[Seahorsewisprer]

That could be a bit pricey, though! I guess we could buy it in bigger quanities.

I think my limiting factor is my lighting. I am going to upgrade to pc, because I found some used.

Tom, what do you have for lighting?

 

[Plantbrain]

I use two sources and perhaops a 3rd if the cost comes down, which it is, PC and HQI's.

The 25 gal tank had 110w of 6700K's on them.

Nothing special.

The 40 cube cold water has a 150 10K HQI.

Light does not matter as much 3-6 w/gal seems fine.
I think the cold water plants will need less.

Warmer waters seems to really kick in noxious micro algae, the main threat in coral and marine planted tanks.

I've seen this in my tanks and in natural reefs and macro plant beds numerous times.

Temprature plays a very dynamic and critical role.

I use simple cheap ag grade ferts, they work just fine:

www.gregwatson.com will get you everything you need.

The Kent iron is EDTA as well as the CMS+ b(we don't need the Boron for marine tanks due to the B already in the salt mixes at high levels, enough to influence alk levels on pH to some degree).

Most all the other trace metals use EDTA, a few use DTPH which is stable to about pH 7.5.

But if you dose frequently, the needs are not great and the chelator does not immediately break down before some gets to the seaweed also............

I'd highly suggest for both your own knowledge and the cost factor, to use the chemicals, not some commercial product/s.

You knwom what is in it, you can use a test kit to measure it, it's always cheaper and it's universally available across the globe.

So everyone is on the same page.........

Regards,
Tom Barr

 

[Fredfish]

Thanks for the link Tom. Exactly what I have been looking for. I see they also carry calcium nitrate.

I understand what you are saying about commercial products and I agree when it comes to aquarium chemicals. This stuff is targeted at commercial aquaculture facilities and as such is a much more economical product. For $15 I have enough f2 to last me a very long time.

Let me see, 10ml/20gx470ml = 940 gallons of medium for algae culture. Since I am only using 2l per week thats... hm... a 36 year supply of algae growth media for about $15. :rollface:

I had never done that calculation before: thats pretty cheap.

The part A has:
.4% iron
.034% Manganese
.002% cobalt
.0037% Zinc
.0017% copper
.0009% molybdenum

The B part is nitrogen, phosphate B1, B12 and Biotin.

I suspect I would have to dose part A in much higher quantities for the macros in my tank than for the phyto so mabe its not so cheap as a macro supplement.

On tank temps, that might be my problem. Over the winter I was running at 78 F, but since early June the temp has been 80 to 82F.

I also need to change out my fluorescent tubes, they are at 8 months now.

Fred.

 

[modemfox]

I also found that when nitrates are zero and phosphates are any number above I get bad cyano outbreaks. Now that i have brought the nitrates back up it gets worse. So i sucked out all the cyano and with one day of nitrates dosed my macro looks 1000 times better and water is so clear you would think i'm using O3.

Of course my fuge is the same size as my main display, so now i have to make sure it is fed or i will have problems with my caulerpas going sexual I beleive from all the info. i've gathered in the last month.

I also will be adding ozone to help my skimmer in the next 2 weeks, that should also get my redox pretty high, for the 100Gallons of water i was thinking a 200mg/h ozonizer would work fine without a controller connected to my skimmer.