"""attack of the killer algae"""

About 6 weeks ago I bought a 5 yr old 90gal with 20 gal sump with water. Good water. About 2 weeks ago I started getting copper colored algae on the sand. It has now left the sand and moved to the walls. It grows back daily, and is getting harder to remove. All water chemistry checks ok. I did put in red slime remover (which I did'nt think was the problem) and it did not help. I did put in some Fiji Gold calcium about 3 weeks ago. I would be thankful for Any help.

 

Sounds like diatoms which will go away by themselves as silicates are used up. Use proper RO/DI water and they won't come back. Use treated water with silicates and it may come back on a smaller scale. Newly setup tanks usually go through this during the cycle.. last a couple/three ish weeks.

 

+1 on Av8 Bluewaters diagnosis that it sounds like diatoms

nothing required IME - let it be and it will go away - sometimes takes a few weeks

also are you testing for calcium? if not, its advisable not to add it to your tank
or anything else thats an additive that your not testing for

Steve

 

Although you didn't disclose if this is a new project, and if you filled the tank yourself (you mentioned the sump had/has water in it beforehand) but--if you embarked upon this tank project 6 weeks ago, and are in the process of cycling the tank--your copper-colored culprit could be diatoms. They're a normal part of the process, and the timing sounds right for their appearance.

If it's on the rocks and the sand, it's a good chance it's diatoms. Once they run out of food, they'll disappear as fast they came.

Give it time.

And, BTW--Welcome to 3reef! You're gonna love it here.

 

Wow. The three of us typing at the same time!

I feel the love.

 

Lol... I do that all the time except Packleader usually beats me to the button(dude is fast) then I feel like a jerk for posting the same thing.

 

Nah, I actually had a few things to do at work sporadically through the day :-/

 

2 people or more with the same opinion, or even identical posts is great for the OP
confirmation is always a good thing in this hobby

Steve

 

Thanks for the answer guys. I forgot to mention the tank had about 50 or so gallons of water with it when I got it. The rest is RO that I put in. I'm checking calcium now. When I put the Fiji Gold in I wasn't and just put in what the instructions said. Which turned out to be a bit too much. The level is ok now.