New fish are dying...can't figure it out.

[Airwaves]

Hi everyone! I'm brand new to the forum. I converted from freshwater to a 36 gallon saltwater FOWLR tank about 6 months ago. I did tons of research before setting up. Bought a nice Eheim canister filter, Reef Octopus HOB protein skimmer, titanium heater, sand and live rock, and two power heads. I went through a 6 week cycling period before adding fish. I did constant water tests. When it was finally time to add the fish, I tested the water right before that, and even brought a water sample to the LFS who also tested it and gave me a thumbs up. I use RO/DI water only. I acclimated the fish using the open bag in tank/cup of water method. My first fish purchase was a small blue tang and a clown fish. Cliche, I know.

The two fish seemed to do very well at first. But that night the clown stopped eating and looked very listless. The next morning he was face down in the sand, dead. The tang was just fine. I thought maybe the clown was just sick to begin with. So I got another one. Same result. So, over the months I did more research, made some minor adjustments based on forum suggestions...but to no avail. Every fish I buy dies the next day, EXCEPT the blue tang that has been there since the beginning. He's thriving and doing very well. But all my other fish die. I waited a couple months and a few days ago I gave it another shot. Bought another percula clown, watched it's behavior closely. It hung out in the bottom corner, but towards the end of the day it was hosting the upper corner near the heater. Never ate a thing. I don't understand why all my fish die except for the tang. I've looked at the situation every which way, and I can't figure it out. Below are my water parameters. As you can see, everything falls in the correct levels.

The only thing l can think of is that I turn off the protein skimmer at night, cuz it's kind of loud. Could it be lack of oxygen? But if that's the case, why is my tang thriving?

Temp. 76F.
Gravity 1.023
Ammonia 0,
nitrite 0
nitrate around 10
pH 8.1

Any guidance would be greatly appreciated.

 

[flower]

Hi,

New fish are stressed, and most won't eat for a day or so until they feel more secure in the new surroundings....and it's also possible the tang is the killer, wanting the territory for itself, for starters...36g tank is unsuitable for any tang.

Try setting up a quarantine tank, and keeping the new fish in that for 4 weeks. It's good for you to do anyway, and it should reveal what the problem is. If the clown does great in the QT, and won't eat and dies in the display...then we can look for the reason. It could just be where you are purchasing fish, some places don't treat their fish well, or they were wild caught in a way that shortens their lives.

 

[Airwaves]

Thanks Flower. There are arguments on both sides about whether or not 36g is suitable for a tang. But setting that aside, the tang has never shown aggression toward any other fish. Unless it happens in the overnight hours when I can't observe.

 

[flower]

Thanks Flower. There are arguments on both sides about whether or not 36g is suitable for a tang. But setting that aside, the tang has never shown aggression toward any other fish. Unless it happens in the overnight hours when I can't observe.

Did the dead fish show any signs of aggression? Torn fins, bloody spots, missing scales...that sort of thing?

 

[Airwaves]

Nope. Not at all. Completely intact.

 

[flower]

Nope. Not at all. Completely intact.

IDK what'ss causing the loss....All I can suggest is that you quarantine all new fish, and see if it makes a difference.

 

[aduvall]

Have you tried drip acclimation?

Also having the clown and the tang in a 36 could definitely cause some aggression issues, however having them die so soon makes it feel likes it's an acclimation issue.

 

[Airwaves]

No I haven't. But I use the next best thing with the open bag and cop of tank water. That really shouldn't be the cause.

 

[kopczynski]

How long do you acclimate this way? How often do you add a cup of water and how much water do you add? Its possible to acclimate this way but the drip method is probably less stressful because its a gradual change. Airline tubing costs like 2$ at a hardware store and you just tie a not to adjust drip length to what you want. I like to slowly increase the rate every 10-15 min and then after an hour let the specimens out. For more sensitive species u may have to do up to 3 hours.

 

[mauler]

I don't think its the acclamation process that's killing the fish especially if it's clownfish. I always just float the bag wait 15-20 minutes then let him go I've never lost a fish doing this.
Do you make sure the fish are eating before you buy them?

 

[Airwaves]

No, I agree. It's not acclamation. I never really checked if they were eating at the LFS. But I'd say chances are after 5 clown fish, at least one of them would be eating well. So I don't think it's that either. What do you think of the protein skimmer and turning it off at night. Maybe lack of oxygen?

 

[flower]

No, I agree. It's not acclamation. I never really checked if they were eating at the LFS. But I'd say chances are after 5 clown fish, at least one of them would be eating well. So I don't think it's that either. What do you think of the protein skimmer and turning it off at night. Maybe lack of oxygen?

If you have power heads, it wouldn't be lack of oxygen... a skimmer is to remove organic solids from the water, not for oxygen. You can keep a saltwater tank without a skimmer, I haven't used one in years.

 

[aduvall]

Flower it was my understanding that skimmers help with the gas exchange as well... But that would kill then that early would it? 5 is a ton!

 

[aduvall]

Have you thought about a Quarenrine to reduce stress and see if they will eat?

 

[jay0705]

The skimmer is a mute point. I keep heavily stocked tanks and none have skimmers. There more beneficial in a reef tank.
now that said, clowns are one of the toughest fish u can buy for sw. Since most are captive raised. So your either buying horrible fish or its the process your adding them to ur tank. Test the water in the bag before you add tank water. My guess is the salinity is much lower than your tank, and ur not evening it out enough, causing osmotic shock.
once thats fixed however the tang in a 36 will kill most tank mates. My kole did and that was in a 55!

 

[aduvall]

^ I still think it's the acclimation process too.

I can't think of anything else that would kill them all the day after.

 

[honu808]

Its either stray electicity in water or acclimation. I would bet acclimation. If lfs water is 1.009 and your tank is 1.020, you will kill them by adding to soon. Im writing this not knowing lfs or your water s.g. Just using as example.
Clown fish are extremely hardy.

 

[jay0705]

Its common for lfs and suppliers to keep low salinity. Its cheaper

 

[aduvall]

Have you tested the water from the LFS before you start the acclimation process?

 

[beth]

It sounds like aggression. Tangs have scalpel like spines on either side of the body near the tail. They use this very precisely and one good swipe will kill a fish. This could easily go unnoticed because their spines are razor sharp and deliever very clean thin (but deep) cuts. Usually tangs are one of the last fish added for this reason. They are territorial and can be deadly if they use those spines. They are called surgeon-fish for a reason.

Also, a 36 gal aquaria is not an appropriate environment fish a tang. Even a small juvenile tang. The small size of the tank limits the tang's need to swim hard and long, causing stress. Stress can result in bullying....which you are seeing with every new addition to your tank. Find a good home for your tang, then add smaller fish to your rather small fish tang. Clown size is a good choice.