MY FEMALE RED EARED SLIDER HA WHATS LOOKS TO BE A BLISTER ORA WOUND NIT SURE. ACCORDING TO THE PET STORE IT MAY HAVE GOTTEN IT DUE TO THE MOVE THE TANK WAS SPLASHING AROUND. 2 SMALL MALES AND A LARGER FEMALE IN A TEN GALLON TANK. WE PUT THEM IN A 45 GALLON TANK. I DECIDED TO TRY NEOSPORIN. SINE I HAVE BEEN PUTTING THEM ON I HAVE NOTICED THAT IT LOOKS LIE IT IS DRYING OUT. AS FAR AS DRY DOCKING HER. SHE GTOES UPO WHERE WE HAVE A LAP ANS SHE THERE FOR A CULE OF HOUSE WITH HER HEAD OUT. NO WATER SO I ASSUMING THAT IT MIGHT BE HELPING. ANY ADVICE THAT YOU CA GIVE THAT WILL HELP. IT STARTED OUT AS PINK NOW NT SO MUCH.
It would help if you could post a picture of the area. Cleaning and applying neosporin daily, then dry docking for a few hours in a separate enclosure (a plastic bin will do--put a towel in for her to hide in) will usually heal small cuts or injuries.
The more important issue is that your turtles are overcrowded. A 10 gallon tank obviously was far too small for three turtles (much too small for any turtle); however, a 45 gallon tank is also much too small for three RES, or even one. A single adult female RES needs a minimum 100 gallon tank. You have three turtles, so you can see that anything other than a very large tank is going to be too small. As a rule of thumb, you can calculate 10 gallons of tank size per inch of turtle--so if your female is 10" and your males 6" each you need 220 gallons of space for them to be housed together. This is why outdoor ponds are often the best alternative for housing multiple RES. You also need a filter than can handle a tank of that size (it should be sized to manage at least twice the tank's capacity), plus proper basking/UVB lights. Skin and shell issues, along with injuries due to overcrowding, are often seen when turtles are in too-small tanks, so I urge you to put together better accommodations for your turtles. The pet store should have given you better advice on the necessary tank size, but pet stores generally aren't very knowledgeable about turtles in general.
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