Cyano in fuge

[Scoot]

I have no cyano at all in my main tank, but its been building up lately in my 'fuge, mostly on the top of the chaeto. Dark brown sheets of the stuff all over the tufts of the chaeto, and it seems to be starving the chaeto out - it starts to brown if I down pull it off (which is hard because it breaks apart).

The owner of the LFS recommended putting a small PH in the fuge to move water over the chaeto, to keep cyano from growing.

Any other suggestions? I've been lighting my fuge 24/7, because a tiny stalk of caulerpa in there has been growing like mad (a half inch a day), going from one small leaf, into 3 large leaves and many smaller ones in just a week.

Anyway, is the PH suggestion on track, or is it the lighting that's causing the cyano growth?

The water params are all great, ammonia 0, nitrite 0, ph 8.2, 80 degrees, sg 1.022, nitrates under 10.

 

[geckofrog]

what are your phosphates?

 

[Scoot]

Never tested phosphates. None of the local stores have the kits.

My chaeto is growing like mad, I'd think it'd be helping to absorb any that are present...

 

[geckofrog]

how much flow do you have going thru your fuge?

 

[Scoot]

Quite a bit - its a sump/fuge, so the whole flow goes through it... I'm guessing around 200Gph. My return pump is 500GPH, taking into account the height (knocking it down to around 250, then I have it toned down a bit with a valve.

The surface of the fuge, in the middle of my sump, is pretty still though, without a PH on it. Very little surface turbulence. The flow seems to be at the bottom.

 

[geckofrog]

Try the power head suggestion. have it point up to the top, so it casues surface turbulence.

 

[seaham358]

Point the PH where the cyno is growing not at the surface.. You want the added flow to break up the cyno and not give it a chance to grow.
PO4 test kit needed, caluerpa will not help with removal. What type of water? test top off water for PO4 also.
Lighting what kind and how old are the bulbs..

 

[Scoot]

Lighting is 2 85w PC lights (the hooded screw-in type that are actually like 18w but put out 85w, whatever). 2700K. I've got to 5100K on the way.

Tap water, treated, well mixed/aerated.

So PO4 (phosphates, right) are what feed cyano? Might have to test for it... what helps remove it (besides cyano?)

 

[roka64]

So PO4 (phosphates, right) are what feed cyano?

Yep, but sometimes, it is hard to get a PO4 reading, since the cyano eats it pretty quick. For a reference, I have cyano ALL over my tanks and PO4 was reading at .1. More than likely, if you have cyano, you have PO4.

what helps remove it

PWCs. I actually ended up removing the sponges from my filter. I had 4 sponges, removed two, did a test 5 hours later and my PO4 dropped to .05. I waited a week for my tank you catch up and removed the other two sponges. Now, I have no cyano....yet....

 

[Scoot]

Now I've got 2 of the 5100K's on the fuge which are recommended over on Melev's site.

Regarding sponges on filters: I have one on both PHs in the main, two in the dual HOB Emperor 400, one in the overflow. I'm getting close to removing the HOB, as soon as I add another 20 pounds of LR I should be set for that... I'll try eliminating the others temporarily to see if it helps.

 

[seaham358]

using tap water may be the problem. test the tap water for po4 and nitrates..

 

[Scoot]

Nitrates in the tap is zero. I'm waiting for a PO4 test I just ordered.

I didnt' have a problem with it for a long time.

 

[Scoot]

Phosphates at tap is reading a clear 0.5.

I can't seem to get a good reading from the tank, it's showing 0.5, but 0.5 on the Freshwater scale. The color indicated isn't even on the SW test scale.

 

[roka64]

It will be hard to test for phosphates with cyano present. It seems the cyano eats it up rather quickly.

 

[Scoot]

Well, the tap being 0.5 for PO4 seems pretty bad - or is it?

 

[roka64]

Yeah, that can't be good.

 

[seaham358]

any amount of PO4 is not good.. You need to use ro/di water to get it out of the tank.
if its in your tap its in your tank, if you use the tap water for your tank.