Originally Posted by sebamd
I'm a newbie too on the care of Betta's but you either got bad luck and keep picking the sick ones on the store or your problem is another contaminant on the water, maybe heavy metals. Do you check the Ph before putting them in? My gf's previous betta died because she forgot to check the Ph and it was too alkaline for the fish (over 7.8) resulting on it dying overnight. Remember, I play by ear here. :P
I don't believe your girlfriend's fish died because of the ph. I have high ph (8) and my two oldest bettas are 2 years & 20 months. Except in RARE cases, fish will adjust to the ph, IMO.
As far as water conditioners go, I use Prime (as do a lot of people on the board). EXCELLENT product that takes care of chlorine, chlorimines, heavy metals, neutralizes ammonia and it is economical using only 2 drops per gallon.