Water good, corals good - fish dying - Help

Harbour · Jun 10, 2015

I have a 12 gallon long.

No filtration other than live rock (did it this way for over 12 years before in another location).

Plenty of water movement that breaks the surface for oxygenation.

Tank is a few months old.

Water parameters using API kit (I kow not the best but it's what I have and use)

PH - 8.0
Ammonia 0
Nitrite 0
Nitrate 0
Temp 78

Have two favites doing great one for over a month and the other a few weeks

Have had 3 clown gobies die and 2 clowns. Seemed to be doing fine then all the sudden one of the gobies bellies up and the next day the other. Same weird thing with the clowns - one bellies up one day, the other the next.

They were not all in the tank at the same time. First 2 clown gobies. they die then 1 goby and 2 clowns (very small)

All happened in the matter of weeks.

2 gallon water change tap water each week (actual water volume of tank is about 9 gallons)

Ideas? Corals doing great fish dying?

RODI is not an option but I suppose distilled from wally world could be.

Thanks in advance as I'm out of ideas - again I'm not new to reefing but this part is new to me.

Harbour

Randy Holmes-Farley · Jun 10, 2015

It might be a fish disease.

The fish show nothing before dying?

Did they all come from the same store?

Harbour · Jun 10, 2015

The very first 2 fish(Clown Gobies) in the tank were from the same store lasted about a week then what I described. Next clown goby from same store. That same goby in tank for about a week then added two Ocellaris Clowns from Petco (I know). Clown Goby dies one day (seemed ok beforehand but was hiding a lot so I dunno) then the next day - one clown obviously struggling when I go to bed then next day both clowns dead!

Perhaps the tank was marred by the first 3 fish from the same store that dies in succession?

Harbour

declanisadog · Jun 10, 2015

I would leave it fallow (fishless) for six weeks, and then try again.

Randy Holmes-Farley · Jun 10, 2015

It could be something in the tank, or poor handling before you got them. We all lose some fish for unknown reasons soon after getting them. Maybe you just had a string of bad luck.

Waiting and then getting different (better quality) fish may be helpful.