Cichlid Fish Forum banner
1 - 4 of 4 Posts

·
Registered
Joined
·
4 Posts
Discussion Starter · #1 ·
Hi All,

About 5 weeks ago I tore down my 75 gallon community tank and converted it to a mbuna tank. Fish have been in it for about a month and doing great. Yesterday, however I just noticed brown algae/diatoms forming on the rocks and glass which has me concerned I am beginning the cycle process again?

I have tested the water repeatedly since the tank has been running and consistently get 0 ammonia, 0 nitrite, and 10/20ish nitrates, (getting 5 nitrates straight from the tap).

The only way I can see my bacteria colony failing is I left my sponges in a bucket of water without an air stone for about 4 days so the sand could settle which is an error on my part. I figured since this media is over 6 years old, the colony would be very established and i could afford some loss.

Anyways, can you get brown algae/diatoms in a cycled tank? The presence of nitrates leads me to believe I am still cycled. I'm just afraid ammonia spikes are incoming and dont want to lose any fish. Thank you for your advice!
 

·
Super Moderator
Joined
·
5,971 Posts
Yes, you can ABSOLUTELY have a diatom outbreak with a fully cycled tank. Those things aren't related, well, really at all.
Diatoms grow out with new substrate (esp. sand) or, if you place a lot of new rocks into an aquarium to change up the decor. Reason is, the fresh sand or rocks haven't been coated all over with bio-slime yet from your beneficial bacteria, making the silica in the sand and rocks accessible to the Diatoms.
Diatom outbreak!
And yes, it will take some time before all of the sand and rocks get coated over with bio-slime (Diatom outbreaks can even happen in older tanks, if the sand has been churned up after sitting static for a good while).
 

·
Registered
Joined
·
58 Posts
I had a diatom outbreak happen years ago after buying a new fish and the aquariumwas well established. As for brown algae, it can happen anytime. I went on vacation and came home to it. In that case, my kid never turned off the aquarium lights, because I hadn't written it down for him to do. I'm in the middle of fighting it in both my aquariums now.
 
1 - 4 of 4 Posts
Top