Damaged tail fins

[paulc]

Last Sunday we introduced 5 more guppies to our 92 litre tank, it already had 3 black widows, 3 platies and 4 other guppies.

The other morning I found one of the older guppies dead with its tail fin really damaged, almost torn off.

This morning 4 guppies are showing extensive damage to their tail fins

I can't see any aggressive behaviour or anything odd during the day. Water quality is fine and I'm feeding them enough so I don't think its hunger

Any ideas?

Thanks
Paul

 

[An t-iasg]

Sorry about your guppy

What are your water parameters? Since you added a group of new fish to the tank, you should check your ammonia level.

I don't know about the one guppy that died That much injury sounds like aggression. Keep watching them. Do you have enough hiding places in the tank? I would also use silk plants instead of plastic plants. The silk plants will not tear the guppy's long fins like a plastic plant can.

For the remaining guppies, they may be stressed by a new environment. Stress sometimes equals finrot. How were they acclimated? Fish need to be acclimated to your water at home, slowly, from the water they were used to at the lfs. I put my fish into a small tank or fish-only bucket with the water they came in. I then add some of my water, slowly, over about an hour. If the container gets too full, use a cup to remove some water, and keep adding your water. After about an hour, I net the fish and put them into the QT tank or aquarium. Don't add all that acclimation water to your tank -- just throw it away.

Watch the remaining guppies. Are the edges of the fins turning black? If so, you'll need to use an antibiotic, preferably in a QT tank. If the fins look like they are smoothing over and healing, I would just do a few extra water changes. Good, clean water will help them heal on their own. Most of the time with my bettas, if they get a small tear in their fins, it heals on its own.

 

[paulc]

Thanks for your help

Water parameters are fine
Another guppy died yesteday and a couple of the new additions have developed ich which I'm treating with medication and heat

Why shoudn't you add that acclimation water to your tank?

Paul

 

[An t-iasg]

When you begin the acclimation, you pour the water the fish came in (and the fish!) in a container, and gradually add your own water. Even if you discard some water during the acclimation, the water in that container still has water that came from your lfs, and I wouldn't want to take a chance on introducing a parasite (like ich), or maybe some snail eggs, or anything bad into my own tank. A lot (but not all) lfs tanks are overstocked and parasites/bacteria/snails etc, could be present. I wouldn't take the risk.