New 120 Gal Saltwater Tank

[boopster]

I have a new 120 gal saltwater tank, it`s been up and running for approx 1 month, live rock(50 to 60 1bs) also a large fluval filter. Recently added some fish, everything tests (nitrates at around 20ppm)o.k. but have lost a clownfish and a damsel, fish just looked good one day and the next day uggggghhh....they died. I have a trace amount of brownish algae I guess appearing on the sand..... what am I doing wrong.

 

[ox5477]

do you have any trace of ammonium or nitrite? If yes, lr is not completely cycled yet

do you use dechlorinated tap water or ro water?

brown algae: Detritus, very typical for a young tank, will eventually dissappear as the coraline algae takes over (the good purple algae)

 

[boopster]

No traces of ammonia or nitrites, I use tap water(we are on a well). Thanks for the info! Should I try to vacuum the sand a little or will the algae eventually disappear. Could I add a goby or a lawnmower blenny, would it help?

 

[ox5477]

Have you ever had your water tested for trace elements? Certain minerals can harm saltwater fish. I would recomend getting the water tested if not tested already, and/or start using ro water (either buy a filter to make your own or can be bought from an lfs).

Keep removing the detritus when you do wc's and it will eventually lose out to the coraline.