Diseased Tank Cleaning

[wentzville]

My fish started to die. I had 14 small fish in a 20 gal tank for 3 or 4 years no problem then they started to die all at once. I took 5 remaining sick fish and put them in another tank and they got better. I did a water change and filter change then added 2 fish from the pet store watched them for 4 days and they got sick too. I put them in my other tank then they got better. So How do I clean this tank? Do I boil my gravel or get new? Do I use bleach on the glass? I have java ferns in this tank do I pitch them or rinse them and put them in another tank?

 

[Zagz]

You could start over with the tank and strip it down and clean it with bleach and rinse it all very well and dechlorinate. BUT you will have to re-cycle the tank. If you know what kind of illness is in the tank you can treat the tank for the illness in some instances. Do you know what the illness is that is killing your fish? Can you describe it if not?

 

[wentzville]

First thing is they lose thier color. They look chalky pale. Then they stay in one spot about 2 inches from the bottom then they die. Going through another cycle is no problem for me. I have 2 other tanks . I already have a spare HOB filter going on my big tank. (Not the one where the sick fish are healing) I just want to make sure that I kill whatever is killing my fish.
so will boiling my gravel and washing with bleach work? Or should I get new gravel? And what about plants can I just rinse them and put them in another tank or can they sptead the problem?

 

[jsoong]

I would bleach the tank & all inanimate objects. Gravel may be a problem - you might not be able to get out all the bleach even with dechlor. Soaking in brine will kill a lot of bugs (but not all). Ditto with boiling (you will not kill spores) unless you use an autoclave or pressure cooker. In addition, if the casue of disease is some form of toxin - you won't get it out of the gravel easily. Some people will get new gravel in this case but it is up to you.

For the plants, you can do a 10:1 bleach dip (for 30 secs, then rinse, rinse, rinse) - might kill some leaves but most plants will recover, or you can grow the plants in a fish free environment for a few weeks & hope that the bugs die without a host (I would do both). Again, if toxins are a possibility, then you'll have to bare root the plants & get rid of the substrate.