Active Member
While I am slowly winning the battle fighting cyano, I am still trying to determine the exact reason why I have it at all.
I have done some thinking and came up with a few possible reasons it may have started:
-Around the time cyano started I added an Auto Top Off. I use RO for my top off, but the container holding the top off water is a BRAND NEW 32 Liter trashcan for a kitchen. It holds about 14 gallons or so. Could it be this trashcan leeching something in to the water?
-Around the time the cyano started I dosed reef calcium into Aiptasia. While it worked in killing the nuisance anemones, the day after I had cyano. This was also the same day I added the plastic kitchen trashcan reservoir mentioned above. Will high calcium levels cause cyano? No, I dont have a Ca test kit, but I can tell you that I only dosed two syringes full. My tank is 50g
-My lighting (Power Compacts) are just under 6 mos. old. Should I change the bulbs already? I keep them on for about 11 hours a day.
-I have kind of slacked on water changes. I do them about every 2 weeks now instead of every week. I only use RO water for water changes and top offs. Water parameters that I can test for (Ammonia 0, Nitrites/trates 0, pH 8.2, SG 1.025) all test about right.
-I have increased flow throughout my tank. I have about 25x flow, and the location where the cyano has one 295gph powerhead aimed directly at it. There are no dead spots in the tank.
I suspect that I will probably be told to buy a Ca and phosphate test kit, and to use a glass (10g) ATO reservoir. If anyone has any other suggestions, ideas, or comments then please let me know.


Staff member
Cryno is really just introduced on rocks. Given the right circumstances in a tank it can proliferate to plague proportions. Good tank environment, keeping lights in the correct spectrium will usually resolve the problem but it takes time.


Active Member
There were no rocks introduced to the tank within one months time of the cyano breakout, and no rocks introduced since then either. Also, the cyano is growing on the sandbed only, and doesnt cover any LR.
Maybe I will try reducing the photoperiod a little more, and then if that doesnt work I will buy new bulbs.