black looking algae?

[osborne]

My lil girls 48 gal has been doing good but all of sudden I have black looking algae. I have dosing with alky/calcium to get the rocks nice and purple. Water checks good always so I dont know. I did have a spotted goby all of sudden disappear. He must have buried hisself and died.

 

[spiderwoman]

Are you testing for alkalinity and calcium? How often do you do water changes? What are the exact water parameters?
Black algea could be cyno. It comes in variety of colors.

 

[osborne]

It does fell like cyno, I maybe feeding them too much, she only has a regular power glow bulb. I always let me LFS check the water and its always good. I normally do water changes week to week and a half bases. thanks

 

[spiderwoman]

What is the flow in the tank? What else is in the tank, fish/corals?
The bulb she has is not enough for anything else but fish. Also how old is that bulb? It may need changing.
I'd very highly recommend
1) do not dose alkalinity and calcium unless you have the exact reading
2) get your own test kits and NOT trust LFS's word that everthing is *good*. You need to know the exact readings

 

[jaymz]

Also LFS usually dont test for calcium. Plus you can cause alot of problems if you get the calcium to high.
A calcium test usually runs about $20 and will last a year. its a good investment.