Red Wag Platy With White Patches And Clamped Fin.

[fishwonderland]

I have a platy that is almost an adult living in a pretty healthy 20 gallon. I just noticed now that they have 3 white patches across the body. At first I thought that maybe it was like some diseases that resemble cotton on the body, but it doesn't look like that. It looks more like the scales were ripped off the body and all that shows is a pale white color. Also, their back fin looks clamped and flat. I am worried that it might be from a Chinese Algae Eater that I am in the process of trying to sell. He has acted aggressive towards one other fish, but only leaving a small dent that healed within a couple days. If you know what kind of disease it might be or if the algae eater could have caused it, please let me know.
The attached file is what the fin looks similar to, but I couldn't upload the white patches.

 

[Byron]

You are wise to get rid of the Chinese Algae Eater; as it matures it gets large, nasty and doesn't eat algae anyway.  It could be the issue here.  But other possibles are water parameters...what is the GH (general hardness) and pH and temperature?  What other fish are in the tank?  How long have you had this tank with fish?
 
Others should be able to help with more data.
 
Byron.

 

[WILDER]

Can you post water stats please in ammonia, nitrite, nitrate, and ph.
How many fish and which type.
 
Have you seen the Chinese Algae sucking on there slime coat.
 
It could be an injury. Clamped fins could be stress if the platy has been attacked
Keep a close eye on the patch for colour. That it does not look pink or red.
Also patches of cotton wool.