Diatom Blues

[thoroughbred]

My 65 gal tank has been up and running for about 8 months. At the beginning I would get diatoms on my rocks and sand so for like 4 months I stoped running my lights. I assumed this was because I was using tap water insted of R/O. About a month ago I got a R/O unit and have since done 4 15 gal water changes (1 per week). I figured things would be fixed so I turned the lights back on and within a few days the diatoms are back and I don't get it.
Params
Ammonia: 0
Nitrites: 0
Nitrates: 0
Ph: 8.2
Sal: 1.025
Temp: 80
I only have a SFE and a pair of small clownfish in the tank so I'm not overstocked and I don't over feed them.
I want to grow some coraline on the rocks and its driving me nuts

Please help!

 

[row]

try testing your phosphates. Algae thrives with even just a trace of phopshates. Everytime u feed, even if u dont overfeed, u are introducing organic waste into your tank, which turns into phosphate.
I am also have a heck of a time with brown diatoms on my sand. I got an R/O unit about 2 months ago but am still having a problem due to phosphates. Im just gonna have to buy some type of phosphate remover for my filter.

 

[geoj]

10 Astraea snails and siphon the sand when you do water changes
PS: you did not post your Cal and KH

 

[thoroughbred]

Sure snails and siphoning will get rid of them for a short time but I want to know how to get rid of them for good.
Also thats all my test kit tests for. Since its only a fowlr I didn't opt for those other testers.
Anyone else out there that will help?

 

[geoj]

Originally Posted by Thoroughbred
Sure snails and siphoning will get rid of them for a short time but I want to know how to get rid of them for good.
Also thats all my test kit tests for. Since its only a fowlr I didn't opt for those other testers.
Anyone else out there that will help?
I want to grow some coraline on the rocks and its driving me nuts
I find other algae will out grow coraline if the Cal and Alk are low

 

[amanda46051]

We basically added a CUC and we put phosban along with Charcoal in the sump. We were able to get rid of the brown stuff.