Why do you have algae and zero phosphate???

[disc1]

I have noticed a whole lot of posts all say the same thing. Huge algae bloom and zero phosphate / nitrate. There is always some heady discussion on what might be causing the algae to grow, but I think it is phosphate / nitrate. The way I see it, if algae is growing, it is consuming PO4 and NO3 by necessity. If it is consuming all of it, then the test will show zero. It's just like the chaeto in the sump, removing PO4 and NO3 and turning it into biomass. Only with cyano or hair algae it's not pretty biomass so we want to be rid of it. But the simple fact remains that you have in this cyano a wonderful PO4 / NO3 sink that is keeping your water clean. So even with a reading of zero for phosphate and nitrate, if you are having an algae bloom, you still need to find the sources of PO4 and NO3.

Any thoughts???

 

[RotaryGeek]

Sounds about right. I have always heard that if you have algae and 0 phosphates its becuase the algae is consuming the phosphate as fast as it is created. So your test of 0 phosphates really means nothing, and you will have to find a way to stop the algae.

 

[d3rryc]

Bingo. You're spot on.

 

[Gilby]

,+1

 

[franklypre]

Just thought I'd join the post with all ya'll locals. I agree with your line of thinking on the green algae, however cyano is bacteria and seems to grow no matter what I do. Stronger flow makes for "hard cyano" I have learned to just let it run it's course and it usually goes away.

 

[muffe]

Phosphate tests are free. Just measure the visible algae in your tank

 

[syrinx]

I have seen this problem grow as sumps are set up for protien skimmer efficiency more than tank health- ie slow flow. Keeping the phos water in the tank to grow algae while the skimmer has more time to take out other wastes, may make water test at zero- but it seems not the best to me.

 

[iamwrasseman]

in order to remove the po4 you will need GFO which get expensive and also you will need to "harvest "the live algae as it contains massive amounts of po4 which becomes fuel for more . if you remove the fuel the algae will subside and you also can cut down on your light regimine a bit as that too will help .

 

[syrinx]

But the gfo will do nothing if the water is stripped before it gets to the sump, by the algae in the tank. I have had good luck with increasing sump flow to give the cheato a even shot at the available nutrients.

 

[iamwrasseman]

if what you just stated then the nutrients wont be available to the cheato either . the GFO will pull out even the smallest amounts of po4 and in turn the cheato will also . my personel lowest readings are when i run GFO but it gets expensive as i said .

 

[syrinx]

Increasing sump flow will make either gfo or cheato beat the tank algae- sorry to be confusing.

 

[Dee12Dee12]

But the gfo will do nothing if the water is stripped before it gets to the sump, by the algae in the tank. I have had good luck with increasing sump flow to give the cheato a even shot at the available nutrients.

Makes sense... Just learned something