Alright so here is the problem. I have two somewhat young adult axolotls in a 20-25 gallon tank (not quite sure). The male is an albino (no more than 5'') and the female is a wild type (about 4" maybe a little more). The filter for the tank is a Penguin 150 and I have a filter sponge placed right after the water wheel to slow the water flow. The female (Ni Ryong) is fine with the current water flow and shows no sign of stress but the male albino (Sa Ryong) does; his gills are sometimes pushed a little forward and when I came home yesterday I noticed that the female's one hind leg is missing so I know the male had something to do with that. Sa (the male) also has been getting these white patches on his tail and I thought maybe he was infected by a fungus (thought maybe that's why he bit off Ni's leg) so for the past two days I've been giving him a low molar (2 teaspoons NaCl in a liter H20) salt bath once a day for no longer than ten minutes as instructed by the website www.axolotl.org which led me to here. The white patches aren't that big (about 2mm in diameter if that) so I'm hoping that I'm nipping the problem in the bud. Also, when I got them from "That Fish Place" they told me that rosy red guppies were fine to feed them until they grew bigger but I've had them for about two months now and I haven't noticed any substantial growth so I'm also a little worried that they aren't getting the nutrition they need which also might be aiding the problem (plus the male seems to get more of the fish than the female so he's being fed more). I've reasoned so far that I need to get some type of worm food (blood worm cubes and such) so tomorrow I'm headed back to "That Fish Place" to pick some up and try it out. Please, after reading all this, tell me if there's anything else I can do (I'm guessing I might need to try a different filter even though the female seems to be perfectly fine even after losing her hind leg). I'm at a bit of a loss here. Oh yeah and the temperature is always kept below room temp (I keep the air conditioner on in my room on at all times and use an ice bottle). Please help me.