Sudden cyano outbreak

[Thade_hicks]

I have had my tank (Evo 13.5) set up for about 4-6 months now and never had cyano, even at the beginning. But I did a small water change and removed about half a pound of macro algae out of the tank and the day after had a decent spot of cyano on the sand. It's been a week and it is just growing and spreading like crazy, what could be causing this. I use RO water and instant ocean reef salt

 

[wculver]

This timeframe is around the time many people have this issue as nutrients build up in the tank over time. This includes Phosphate and Nitrate. Probably by taking some of the algae out it upset the balance and the cyano started going.

I'm not sure what your setup looks like but there are a few options.
- If you are setup for filter socks that usually helps but personally I only use them if something is really bad because you have to change them every few days. I'm not familiar with the tank you have so you may have to rig something up or perhaps there is an add-on you can use.
- Using some restraint on feeding the fish is also important. Try not to let extra food chill that the fish don't finish off.
- There are other options but before I unload them we really need to know what the levels for Nitrate and Phosphate are.

 

[Thade_hicks]

This timeframe is around the time many people have this issue as nutrients build up in the tank over time. This includes Phosphate and Nitrate. Probably by taking some of the algae out it upset the balance and the cyano started going.

I'm not sure what your setup looks like but there are a few options.
- If you are setup for filter socks that usually helps but personally I only use them if something is really bad because you have to change them every few days. I'm not familiar with the tank you have so you may have to rig something up or perhaps there is an add-on you can use.
- Using some restraint on feeding the fish is also important. Try not to let extra food chill that the fish don't finish off.
- There are other options but before I unload them we really need to know what the levels for Nitrate and Phosphate are.

It's an all in one tank. And I only feed twice a week so no excess food

 

[wculver]

It's an all in one tank. And I only feed twice a week so no excess food

Well certainly a small amount of food but ultimately you have a problem with excess nutrients based on what you mention. So best option would be to keep up with water changes to reduce the nitrate and phosphate which will in turn eventually eliminate your issue.