Newbie with brown Algae, Please Help!!!

[Army.Veteran]

Hello All, I currently have 3 tanks that are all fresh water. 150 gallon, 55 Gallon, and 30 Gallon. I have the 55 set up for about 1 1/2 years and never had this problem ever. I bought the 150g and the 30g when I bought my new house(Different City). I noticed it in my 150g first. I turned off the light for about 1 month. it went away, then I turned the light back on(No more than 6 to 8 hours a day) and it came back. I do not over feed at all. I then noticed it in the 55g, and 30g. I have bought a RO filter. Just hooked it up this weekend to the washer faucet. I did a water test on both Ammonia and Nitrate, It came up with significant less Ammonia, but still had. And Nitrate had a large number. I have done water changes and turned off the light, it does get rid if it, but it sucks that I can not have the light on. If I turn it on everyday, it will get all over the tank and decor. I have talked with people and they said maybe i have to much phosphate in thew water. Any info or help would be great, I would like to remedy this asap. Thanks.

[peanutbowl]

a picture would help to identify the brown stuff, but if the tank is new(<6 months or so), it is likely diatoms. if this is the case, it just means there is a source of silicates in the tank. new glass, silicon sealant, rubber parts, etc are all sources in a new tank. they can be cleaned without too much trouble at water change time. but if they really bother you, you could get some SAE's, they will make pretty short work of them. i got some ramshorn and pond snails in my tank that hitchhiked their way in with some plants. they cleared the tank of diatoms in about a week.