New tank. 4 diotom bloom? HELP

[RaeRae]

So this is my problem. Been doing this several years now. Going on six. Thought I was ready to get out then my boss asked me to set up a 90 at the office. I have had 5 tanks in the past and have always used live rock. Well for this set up EVERYTHING is new. Dry rock and all. I have gone threw a cycle with a full diotom bloom at the end. All my perm read 0 nitrate, nitrite, ammonia, kh is right and pH is on. Since I have two clowns and yellow and powder blue, cleaner shrimp, acans, blasto, candy cane added. Tank has been up now for almost three months. Once or twice a week I get a small 30% or so diotom bloom on the rocks and sand. I use a four stage RO unit and my tdm is 0. I have bounced my water perm off my local LFS and all match my findings. I have lost a frog spawn and a hammer coral last week I believe to this diotom issue. Can this dry rock still be leaching out and giving me silicates? And if so how long can I expect this to last?

 

[RaeRae]

Bump

 

[Nurse Payne]

I did a 300 gallon set up similar to this, using all "new" medias. If your tank does like mine, you're almost finished. I would guess it took 4 months for the diatom and hair to appear and disappear. I added clean up crews twice during that time and now, it's perfect.