Phosphate's in the Aquarium question

[CloudIX]

I know that phosphates contribute to algae growth, this is old news to me. What i was amazed to learn is it can directly inhibit calcification of corals. I don't really understand how this works. Ive tried to read some of the papers on this subject and it quickly gets over my head.

Can someone explain to me how this works and at what rate this happens?

Does it always stunt a corals growth or does this only happen at very high levels?

 

[poolkeeper1]

It depends on what you read, May be the effect of Pesticides used on land that are raising the Oceans Phosphate levels by the amount of Po4 from water runoff that goes back into the Ocean that is caused a receeding growth rate. Phosphate promotes Algae growth (The bad kind) not the Algae in the Corals that produce the Sugars that Corals need to grow, This is a very basic answer and may not even be what you are asking but this is one way Po4 effects Coral growth. JMO
Bill

 

[GT_Jacket]

Some claim a LITTLE PO4 and NO3 makes their corals look much better...

Should dead 0.00 of these be the goal or try to balance so just a touch of each exists???

Brett

 

[poolkeeper1]

Correct

Correct

Some claim a LITTLE PO4 and NO3 makes their corals look much better...

Should dead 0.00 of these be the goal or try to balance so just a touch of each exists???

Brett

That's Correct It's some kind of formula that you must have Some Nitrate for some Phosphate to be present, I think It's called some kind of Theory by a well known Reefer. But from what I have read It works and Absolute Zero is not the Goal IMO
Bill

 

[CloudIX]

If the goal is not 0, but we don't want it to be detectable on our test kit's. What should we shoot for? I use the Hagen test kit for PO, and clear is 0, very light blue is the next step up (i think .25). should i be shooting for something in the middle of the 2? Wouldn't running GFO or vodka dosing bring it to 0, and that is not what we want? I'm confused here.

 

[USAF427]

Its not terrible surprising... same thing happens to your bones from too much Cola or from Renal disease (there are other reasons for this too, but thats more medicine.)...
Phosphates are negative charged Anions, and Calcium is a positivle charged Cation... It has been a long time since I've done a chemistry class, but I would venture a guess that elevations of phosphates would bind calcium and make it unavailable to the Corals. In human bone cells there are also hormonal influences, and I don't know if there are signaling chemicals that would be analogous in corals, so maybe there are other reasons for this as well...
thoughts?

 

[GT_Jacket]

If the goal is not 0, but we don't want it to be detectable on our test kit's. What should we shoot for? I use the Hagen test kit for PO, and clear is 0, very light blue is the next step up (i think .25). should i be shooting for something in the middle of the 2? Wouldn't running GFO or vodka dosing bring it to 0, and that is not what we want? I'm confused here.

Bill - is this what you were thinking of?

http://en.wikipedia.org/wiki/Redfield_ratio

CloudIX - you don't want anywhere close to .25 (ppm) PO4. Under .03 is recommended to inhibit algae growth. Yes, you can get your tank too clean with various ULNS methods. This is why most have amino acids in their line as "food" for the corals.

 

[jdegrasse]

My educated guess is that free phosphates tie up free calcium as calcium phosphate, which is insoluble at the pH at which we keep our tanks. This may be a factor as to why the water becomes more clear as nutrient levels go down.

I'm also guessing that calcium phosphate is one component that causes the "bad" algal blooms as it does in nature from farm runoffs.

Whether in our diet or in our tanks, the relationship between soluble phosphorous and calcium is a delicate balance.

HTH,
JD

 

[CloudIX]

Thanks USAF427, that helps alot. Why don't they just say that in the articles. Much easier to understand it that way.

GT_jacket. Why in the H$!! does the test kits go from .0 to .25 (i think that was the scale on my kit) if you never want over .03. Kinda makes the kit useless don't you think?

 

[jdegrasse]

I'd also add to GT_Jacket's point that adding nitrogen and phosphorous as part of a food-source (e.g. amino acids) is much better than having it soluble anyway in terms of controlling the tank. I'd rather remove all soluble phosphates and nitrates (it is constantly being produced anyway, so its never truly "0") and feed my guys the nutrients they need in controlled amounts.

 

[CloudIX]

so what kind of amino acids are you using?

 

[jdegrasse]

I don't know if that matters. Brightwell Aquatics as well as Kent both have products, just to name two.

 

[USAF427]

Thanks USAF427, that helps alot. Why don't they just say that in the articles. Much easier to understand it that way.

GT_jacket. Why in the H$!! does the test kits go from .0 to .25 (i think that was the scale on my kit) if you never want over .03. Kinda makes the kit useless don't you think?

NP... I just hope I am right and not just talking out my backside

 

[GT_Jacket]

Thanks USAF427, that helps alot. Why don't they just say that in the articles. Much easier to understand it that way.

GT_jacket. Why in the H$!! does the test kits go from .0 to .25 (i think that was the scale on my kit) if you never want over .03. Kinda makes the kit useless don't you think?

Not all PO4 test kits are designed for the levels reef tanks desire... maybe they are for planted tanks for something.

Check out the Hanna Checker the club just got for use and see how you like it. It reads down to PPB I believe.

Brett

 

[CloudIX]

cool, i may ask to borrow that.

 

[trueperc]

Two things to consider on this, first off our test kits only read inorganic phospate which from my understanding is what you want none of. What corals and such like is a little organic but not to much.
Here is a great read on it by Randy
http://reefkeeping.com/issues/2006-09/rhf/index.php

 

[CloudIX]

yea that is what i was reading that started all these questions. When you go to the link where he talks about it inhibit calcification of corals is the part that i got lost on.

 

[poolkeeper1]

Po4 Level

Po4 Level

If the goal is not 0, but we don't want it to be detectable on our test kit's. What should we shoot for? I use the Hagen test kit for PO, and clear is 0, very light blue is the next step up (i think .25). should i be shooting for something in the middle of the 2? Wouldn't running GFO or vodka dosing bring it to 0, and that is not what we want? I'm confused here.

I keep mine at around 12PPB which is 0.036PPM on the Hanna Phosphate Checker, And have some success with SPS and I keep it at these levels with the use of Eco-Bak alone and do not use any GFO.
Bill:wavehand: