chemistry/algae question

[Steve W]

I am having a problem with what I think is cyano proliferation. For the last week to 10 days the sand substrate and a few small rocks on the bottom have been covered each day with a thick slime coat of dark brown algae/goo. Today it had moved up onto the lower rocks. I'm assuming it is cyano, but I'm not sure since I've never seen it before. I am also having considerable green algae on the glass.

I have been siphoning it out daily but it keeps coming back.

I have checked my nutrient and chemistry levels and getting results that seem good.

Ammonia - 0
Nitrites - 0
Nitrates - 0-5 mg/l
Phosphates - 0
pH is a little low ~8.0
Carbonate hardness - ~1.7 to 2.5 meq/l
Calcium - 435 ppm
Salinity/s.g. - 1.025

I ran these tests at home and then had these checked at Coral Reef and they got similar results. I haven't had any significant changes in flow conditions. My temperature is a little higher than previously - 79 degrees with the new heater now versus 75 previously . No significant changes in lighting. I have no way to test magnesium but assume that it should be good. I'm using saltwater from the Coral Reef and haven't changed that. I've done 3 -20% water changes in the last week due to the heater implosion.

I'm running about two ounces of high grade (laboratory-grade) AC guaranteed to be phosphate-free and have added a poly pad since the heater issue but the problem seems to have gotten worse. FYI - This started before the heater problem.

Any suggestions? thoughts?

Another question - what should the carbonate hardness be for best growth of stoney corals?

Steve W.
24 gallon Nano w/ 150w MH

 

[Steve W]

bump

 

[macclellan]

Cyano always goes away on its own in my experience. Siphoning it out could just prolong the process.

 

[Steve W]

Any idea what caused it?

Will it hurt my corals if it gets on them?

Steve W

 

[Engloid]

From what I have heard, flow can have a lot to do with it.

I used that chemi-clean stuff that's supposed to wipe it out, and it is amazingly good. It will eleminate it all within 2 days.

I would say that if you have other issues, to just let this one run its course for a while, but all your tests are good, so you may be fine to go ahead and use it if you want to.

 

[vwtanker]

Your nutrient levels could be locked up in the algae causing them to read 0 or low on your tests. More frequent water changes with good water, a refugium, or a probiotic system could help.

 

[GPhiAce]

How long has the tank been set up? What flow do you have? I would increase the flow and gice it some time. Like joel said, it usually goes away if you have good flow and a well cycled tank. It may also be diatoms, but without a pic, it is hard to say. Sounds like a temporary issue if those parameters are real. May may wanna check your Mg.

 

[Engloid]

The tank is cycled well. It was moved a couple months ago, but I saved most of the water for the move. I've got probably 300lbs of live rock and it's covered in coralline algae, so I'd imagine things are pretty stable.

I may rig up a bypass so that I can Tee off of my return pump and run one side back to the inlet side of the sump. That is really the only way to increase flow through the sump since my overflow box is already flowing its maximum.

I put a Koralia 3 in the sump to help move water around, but since this stuff is only growing on the surface, I'm thinking it's photosynthetic. I've shut the light off on the sump for a few days so far and will probably go 5-6 before turning it on. Hopefully, that will kill it off.

 

[macclellan]

Steve W = Engloid?

 

[Engloid]

Steve W = Engloid?

oops. wrong thread. :wavehand:


I guess it's a bit related though.

 

[Steve W]

Tank has been set up for five months. The flow is from the pump on the Nano + a Korelia nano powerhead.

Problem seems to be going away.

Steve W.