Clown has lost the black edged of its tail!


Reefing newb
I have 2 clowns, a damsel, a goby, and a coral beauty angel. I noticed today that the black edge of my larger clown's tail is missing. I originally had two clowns, but one jumped and died, I replaced it with one that was smaller several weeks ago, the fin problem is with the bigger original clown. Other than the new clown, the angel is the newest fish, but even that one has been in the tank for over 2 months without any aggression issues. What's weird is it only seems to be the edge where the black was. The rest of it's body looks healthy, no ich or dull color. I don't have a power head, just a HOB filter and heater. Sorry if the pics are a bit blurry, little bugger doesn't stay still...anyone else ever had such and issue? I know disease usually looks really messy, but this doesn't look that bad, just the missing tail edge.

My latest readings are Ph-8.0, Amm 0, Nitrite 0, Nitrate 15, temp 78, Salinity 1.024, and tank has been consistently at those levels for months.


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May be aggression between the clowns, but I suspect the DAMsel. As long as the fish is eating and otherwise healthy, it should recover. What kind of damsel do you have?
I agree. Keep an eye on aggression esspecially between the clowns and the damsel. Is the tank a 20 gallon as in your description? If so, it is quite possible overcrowding causing it. 5 fish in a 20 gallon seems a bit on the high side to me.
Thats all good unless you have a bacteria issue or cheap food. Cheap food tends to not satisfy their color enhancement and lighting changes also changes the eye perception. I would argue that the fin loss is not just a fish compatability and more of the lines of an underlying issue.
Damsel has oddly always been non-aggressive, contrary to all the warnings I have received (possibly because it was the smaller of two I had originally purchased), the food has been the same all along, and the lighting is reef lighting high output, and was put in place months ago. My theory is indeed a little overcrowding, I had an issue with my 55 leaking months back and moved everything into this 20 long as an emergency, but up till now everything has been so perfect in this tank, I haven't wanted to fix what wasn't broke so to speak. I have recently been planning to increase the tank size, and this kind of cements it. I think the Angel maybe is getting a little more aggressive as it grows, and more room would keep it from being so territorial...I just hope the Clown is ok until I can, and that it recovers ok.
I didn't even realize we were talking about a 20 gallon tank. Of course you are having aggression issues! Get those babies in a 55!