Clowns died but Damsels are fine

[Tyler Couey]

So I am very new to keeping a saltwater tank. I caught a large marine hermit crab at the beach and I wanted to keep it. I followed my lfs advice and bought a 20g tank and kit and set it up. I put live sand in it and I bought a few cases of the water that they said was straight from the ocean. (I did that because they said the tank wouldn't have to cycle or anything and I could put the crab in a few days after and get some fish). So I went home, set everything up and put the hermit crab in the tank. It was perfectly fine after a few days I went to my lfs and got my water tested. Everything looked perfect so I got two damsels to make sure everything would be okay before I got a pair of clowns. After the damsels and hermit crab lived for about i week I went to go get a clown. They all lived happily for about a few days and then all the sudden the crab came out of its shells and stopped moving and died within a day's time (it wasn't molting and it had been out of the ocean for like two weeks by this point). So I immediately got the crab out and then all was fine for another three days. I went to the lfs and got my water tested again and all was perfect and I was talking to them about getting more fish and they said it would be fine if I put two more clowns in there. So I did. After about two days the original clown turned pale, at the surface breathing rapidly, and looked slimy so I called the store, they said to come in and they gave me this formaldehyde treatment to dip the clown in and gave me proper instructions on have to do it. I went home and did it and the clown died shorty after. (I did it EXACTLY how I was told and they demonstrated). So they said to read the intructions and put the correct amount of the treatment in the tank so I did. A day or so after, I noticed the other two new clowns were staying at the surface not doing much, hardly eating. I assumed it was because they weren't used to the tank yet and from the research I had done this was typical behavior. They both stayed this way for about a week and a half then I woke up one morning with both of the new clowns dead and they never showed the symptoms of the first clown. Meanwhile, the damsels have been fine and I have done proper water changes and got my water tested more times than necessary at my lfs. I don't understand what is happening but I need to figure out how to fix it so I don't invest more money in my tank for new fish to die. Please help and thank you for taking the time to read this, I know I write a lot. Thank you.

 

[lmforbis]

The clown sounds like it had brooklynella. This is a marine parasite. Clowns are particularly susceptible. Once it is in the tank you need to treat all the fish but also the tank needs to be kept empty until all the parasites die off. The other clowns, if they were all from the same store also probably had it. The damsel probably was harassing them as well which weekend their immune system hastening their demise. Not sure how the crab fits in but it may have just been because he was in captivity.

 

[Tyler Couey]

But the other two clowns didn't show the symptoms of brooklynella. They looked fine they just hung out near the surface and didn't breathe rapid or look slimy or anything. That's what confuses me. But how would I go about getting rid of it? Do I need to get rid of the damsels and leave the tank empty for awhile?

 

[lmforbis]

Yep. You are best off getting rid of the damsels no matter what. They will harass any new fish you try to add. Especially in a small tank. Leave the tank fishless for 6 weeks, I think, for brook.

In the future a small quarantine tank is a good idea. Quarantine all fish for 4 weeks to make sure they are healthy before adding to the tank.

 

[beth]

The 20 gal tank may be adequate size for 2 clownfish but not much else. Also the LFS gave you bad advise. Fish tanks MUST be cycled. MUST BE.

Saltwater fish keeping is a hobby that requires the hobbyist to invest research and time into learning first before diving into acquiring live animals. You have to have a sense of confidence in knowing what you are doing before keeping a salt tank. It's good to get advice but you have to be in a place in the hobby where you know the difference between flaky advise and sound advice. And, the only way to do that is to have some knowledge yourself. The setup you have with the advice you got, is wrong.

I would suggest spending some time on forums such as this one or the many others out there and doing self research, asking questions, etc. A very good beginning book is "The Conscientious Marine Aquarist". You will not go wrong with that as a reference as it will guide your through the process. Even getting salt water from the sea is pretty questionable.

Don't rely on your LFS to test your water. When they say, "Your water is fine," you don't really know what that means. Learn this yourself. Test yourself. Now the water may be ok because it sounds like you got 100% live sand and have live rock, but the animal load was way too much for 20 gal and certainly too much for a new tank.

Clownfish have to be a mated paired otherwise the larger (female) will harass the smaller (males) to death. Did the store sell you a mated pair? I bet they didn't. You can not keep 3 unrelated clowns together in a tank, let alone a tiny 20 gal.

If you are really interested in the long term of getting into this hobby know that you have to be invested in it. If you're not, then stop now. However, if you are, proceed slowly. Spend time doing research before taking your next step. The reference book I suggested above is a great start. It's a good read with lots of illustrations, diagrams, explanations, details presented in a good way for beginners.

Forums are a great place to run things by if you feel uncertain. Patience and research is the only way to success in salt water fishkeeping.