Algae problem

[Sniperhank]

I don't recall RO/DI is being used here or not...if not it would likely be a great help. How to correct this issue has already been stated, but I will atleast summarize.
-cut back on feeding. feed every other day, if possible, and do so minimally. Feed very small amounts and make sure all is consumed. If able, remove unconsumed food.
-cut back lighting as much as possible. I'll assume that there are corals and you will need some light. Try to cut down to 6 hour lighting schedule. If corals aren't happy increase to 8.
-Do daily water changes. Prior to water changes, scrape/remove algae. Remove as much as possible. If able, pull entire rocks out and scrub the algae off.

 

[cmdw4587]

I had this problem and got rid of the cyano by using multiple techniques.

I only ran my lights for 8 hours on Wednesday, Friday and Sunday. I did this for 2 weeks

I did a 10% water change on sunday and Wednesday cleaning as much off the rocks as I could each time.

I also used instant ocean natural nitrate remover at double the recommended dose (this is ok to do) once a week for 3 weeks then dosed at the normal level for 3 more.

Doing this I eliminated the cyano and haven't had a problem since. I do a 10% water change every Sunday and only feed small amounts Monday Wednesday and Friday. My lights are on daily for 8 hours.

Hope this gives you some ideas and maybe it will work for you too.

 

[cmdw4587]

I also only use RO/DI water in my tank