ok so a serious of mistakes have lead up to this. first off i had moved a betta into a tank that had guppies in it prior and i took 75% of the water out and changed it beofre adding him. secondly i added a divider and a plaket male betta to the same tank and the plaket jumped the divider even with it an inch above the water and tore my new boys tail to pieces. now its healing up with i think is why its whiteish clear but due to my absence on vacation and an over feeding by little sisteri came back to his tail turning black. i did a small water change and gravel back but his tail isnt healing anymore. i think he has fin rot so i changed 3 out of 10 gallons from his ten gallon tank where he is now the only fish. is there anything else i can do with out harming the plants or biofilter? and will his beautiful spade tail ever grow back properly?