Dying fish - Semi new tank

[Protodad]

Need some advice. Lost two fish overnight and probably two more tonight. 120g tank. About 6 weeks old. Nitrates are around 7ppm. No way to measure phosphate. Slight amonia on the test kit. Mostly dry rock. Some live plus dosing microbacter.

Fish show no sign of disease but all looked stressed and the ones I’m trying to keep alive have all bleached out. Caught the most recent tang and acclimating to my “good” (small) tank with an airstone but he was hiding all day and I think the only reason he got out was because of how bad he’s doing.

I’ve dealt with disease before, what’s the plan for fish that don’t show signs of it?

 

[ScottR]

The first alarm is the presence of ammonia. I’d wait until you’re certain your tank is cycled before adding new fish. It’s always a good idea to QT fish as they can carry disease but show no visible signs.

 

[Protodad]

I swear it showed zero before I added the first one several weeks ago. It’s an api kit so I’m questioning it now but it’s had 4 weeks of microbial dosing

 

[NexisG]

How many fish are currently in the tank and what types. When did you add them. What are the ammonia and nitrite numbers since both are important. Any heavy breathing from the fish. Even if not adding more aeration is never a bad idea. Are the fish eating? Is the water clear with no cloudiness? Any signs of physical damage? Biggest thing you can do is big water changes with fresh mixed saltwater. While that doesn’t fix everything it does help with lots of problems. Make sure salt is mixed properly before adding it.

 

[00W]

How many fish are in there and what kind of system do you have set up?
If they are all struggling that badly there is a poisoning issue going on. Ammonia most likely. Let us know

 

[Jekyl]

Sounds like you went too big too quickly. 6 week old tank max should have 2 or 3 fish. Do a large water change and get your levels down. If ammonia keeps showing up do more changes.

 

[Protodad]

4 fish
Blenny. Two tangs. One angel. All on the smaller side. Added over 2-3 weeks.
Ammonia is less than 0.25ppm but might be more than zero. API test kit. nitrate less than 10ppm.

No heavy breathing. No signs of disease. Just heavy bleaching. No physical damage. The fish that did the harassing was the first to go.

it’s a 120 so I did a 20g water change and planning to do another tomorrow. Have more salt on its way.

trying to decide if I should isolate the fish I could catch (not easy) or add it to my good tank.

 

[00W]

I have a 75 with 2 fish. Set up for over 2 years. I go super slow.
But anyways let's try and help.
Water change?
What salt?
Awesome surface agitation?

 

[Protodad]

Sounds like you went too big too quickly. 6 week old tank max should have 2 or 3 fish. Do a large water change and get your levels down. If ammonia keeps showing up do more changes.

Did a 20g today and planning on 20 tomorrow. Trying to get more salt.

 

[Protodad]

I have a 75 with 2 fish. Set up for over 2 years. I go super slow.
But anyways let's try and help.
Water change?
What salt?
Awesome surface agitation?

A lot of flow. Mentioned other parts in other posts. HW reefer salt.

also, not my first tank. I’ve been at this on and off for 15 years. The ammonia coming “back” might be a bad test kit but I’ve never had this kind of reaction from the fish.

 

[Jekyl]

Using RODI water? We're the rocks free of all biological?

 

[Protodad]

Using RODI water?

7 stage BRS with zero tdi coming out.

 

[00W]

What equipment?
Go to your LFS and pick up some IO. It'll do for now. Cheap and mixes fast.

 

[Protodad]

I don’t have my gfo or carbon set up so I can’t strip the tank until Monday. Really looking for advice on keeping a fish alive who shows lots of stress and whitening but no disease.

 

[Jekyl]

Water change is the quickest route probably. Make sure anything dead gets removed immediately

 

[Protodad]

What equipment?
Go to your LFS and pick up some IO. It'll do for now. Cheap and mixes fast.

I’m not sure what you mean by equipment. I have a protein skimmer, sump filter and lots of rock. I have gfo and carbon coming in a few days and the reactor to run them. I have about 20x turnover through pumps and power heads while it’s fish only.

 

[Protodad]

Water change is the quickest route probably. Make sure anything dead gets removed immediately

I did and working more water changes