I have been told a number of different things about water changes and just wanting everyones opinions please.I have 125 freshwater using 2 emperor 400 HOB's with a stock list ofStock list includes: 1 Andinoacara Stalsbergi(S/A) (True Green Terror), 1 Heros SP Super Red Severum(S/A), 1 Gold Severum(S/A), 1 Placidochromis Phenochilus (Africa)(Star Sapphire), 1 Vieja Synspilum (S/A)(Fire Head), 1 Hypselecara Temporalis(S/A) (Purple Chocolate),1 Microglanis Cf. Iheringi(S/A) (Bumble Bee Cat), 1 Jack Dempsey(C/A). and most fish are in the 6 to 7 inch range and was told I can keep these large fish in a 125 gal as long as I do 50 % water changes once a week. so the last 6 months I have been doing just that and parameters are always fine but just recently am treating tank for slight case of fin rot. All LFS tell me that 50 % is too much and that 15 to 20 should be enough.Just wondering why the fin rot popped up all of the sudden and have read that fin rot is sometimes caused by overstocking, but thinking if I do the large water changes this should be ok. I would like everyones thoughts on this Thanks.

