diatoms blooming again...

rob s. · Jun 2, 2020

So i have a 20 gallon reef tank and it relatively new (about 6 months). within the first 3 or 4 months my tank exploded with diatoms which as i understand is very normal. About 2 weeks ago i started seeing another bloom starting in one corner of the tank. I readjusted the flow thinking maybe it was due to low flow in that one corner but it seemed to make it worse. I have re-adjusted the flow back to how it was but the bloom is getting bad. I'm wondering what other than time can be done. I was doing weekly 40 percent water changes but that hasn't seemed to help. What if anything other than time can i do to make this go away? I feed every other day and only have 2 small clowns and a fire shrimp in there plus several frags. am i just suffering from more "new tank syndrome" and it will eventually die off? Will they effect my water quality or corals? Thanks for any help.....

Webslinger · Jun 2, 2020

are you using rodi water?

rob s. · Jun 2, 2020

yes i am

rob s. · Jun 2, 2020

Webslinger said:
are you using rodi water?

rob s. · Jun 2, 2020

i am and all my water parameters are good....I'm worried if i stop water changes which was suggested to do for a while my water parameters will get out of whack and make things worse?

Webslinger · Jun 2, 2020

new tank?

rob s. · Jun 2, 2020

Webslinger said:
new tank?

yes about 6 months old but its already gone thru a bloom and cleared up and now its happening again. What causes this other than silica that i think they eat.?

andrewey · Jun 2, 2020

Couple options here. One, this happens during the first year in new tanks. Usually people get one bloom, but it's not uncommon to get multiple blooms during the first year.

Additionally, have you added anything new to your tank recently (rock, plastic, etc.)? If so, these can fuel a second diatom bloom.

It could be your RODI filters need replacing. Do you have a TDS meter?

It could also be something other than diatoms such as certain species of cyano or dinoflagellates. Many are hard to distinguish from diatoms with the naked eye.