Cyanobacteria

[Labmonkey]

I am having issues with cyano on parts of my sandbed, some of the rocks, and back wall of my 75g. I am contemplating a full tank blackout as current efforts do not seem to be working. I have been vacuuming out the cyano and any detritus in the sandbed for the last few days, while reducing my feeding, but it keeps coming back and seems to be spreading. Waterflow seems good, I have an orbit 4 set at 60% pulses plus my return at about 1400 gph. I mix my own saltwater and the TDS on the outlet of the DI resin is reading 1 ppm. Apart from this, everything else looks amazing. My phosphates are probably a bit high, but I cant imagine it is the culprit for this much cyano.

Current parameters:
pH 8.0
Temp 78F
Phosphate: 0.12 ppm
Nitrate: < 5 ppm (I need a better test)
Akl: 9.6 dKh
Sandbed Par: 180-200

 

[Formulator]

You could use some sand bed CUC to get that sand turning over regularly. Nassarius snails and conch are great. Sand sifting gobies are even better if you have the bioload to spare. Regarding nitrate and phosphate, I’ve found its not always the value, but cyano tends to pop up with instability in those nutrients, especially after a big swing. This can be downward or upward. I agree the phosphate is not high enough to be concerning. Blackouts can work if you are at your wits end.

 

[Labmonkey]

Ya I have about 25 nassarius snails. Could be a phosphate swing. Last time I checked my parameters, about 2 weeks ago, they were 0.03.

 

[Dburr1014]

Normally it's imbalance of nutrients and/or lack of flow.
And the places where you're getting it, how is the flow there?

 

[Labmonkey]

Flow seems pretty good, it’s strong enough that it’s causing the bacteria to grow stringy and actively move in the current