Sick Fish

[k10ike]

We have a 30 gallon tank running since July (saltwater) We have had various fish die with no outward signs of any illness. Had the water tested Perfect. We now have 1 clown (about 2"), one Dottyback and a firefish all about 2" insize. We added a yellow tang December 24th (about 2 1/2") The tang (our second) is not doing well again water tested 8.2 PH, 0 nitrate, 0 amonia, 5.0 nitrate salinity and temp right out. Any suggestions as to why this is happening.
The clown fish has been in the tank since day 1 and doing great! lost a hi-fin cardinal, large yellow tang , and one more i think the name was something angel fish anyway, they just stop swimming and then about 24 hours they die. treated with stress coat and also tied pimafix at the suggestions of the "fish expert" at the store. No luck with either.
Change our fitler every 2-4 weeks water change 3-4 weeks.
any helpful hints? It is very distressing to not know what the problem is.
Thanks

 

[willtang3000]

whats the salinity?

 

[WILDER]

How many gallons is the tank and that is a high nitrite reading, how long has the tank been set up,and when did you add the fish before the tank had cycled.

 

[k10ike]

whats the salinity?

I see I typed nitrate twice nitrate level is 5.0 NITRITE is 0
the salitity is1.022 30 gallon tank running since July 24th.

 

[Durbkat]

Well seeing as this is the tropical emergency section and your asking about saltwater fish I'd recommend you go here in the saltwater section of this forum http/www.fishforums.net/index.php?showforum=35 .

 

[WILDER]

Do you no when they stop swimming do they lay to one side.

Do the get bloated, then lay on the floor, or do they swim laying over to one side, can they maintain there balance in the water before they stop swimming, also do scales stick out like a pinecone, any signs of flicking and rubbing against objects, what do you feed the fish, also what does it look like when the fish goes to the toilet.