Tsuh Yang, My experience with malachite green has always been pretty good. Being a copper dye, I doubt that it has gone bad if you kept it in a dark bottle and air tight. I've always used the recommended dose with formalin (2 drops/US gallon), but this is very hard on scaleless fish and plants. You might be better off using the old 1950s method: raise the temperature to 85ºF (30ºC) and do large water changes every other day for a week to 10 days. Mike Wise Piabinha@aol.com wrote: > a few days ago, a small ick infestation broke out in my 55-gallon amazon tank > among some tetras. yesterday, i dosed it with some malachite green that i > found in my supplies, which is a few years old. > > 1. will this still work even though it is a few years old? > 2. will this harm plants, snails, naked catfish? > > i've always heard that malachite green was a very effective medication against > ick. the label says "use half the amount indicated for tetras and catfish," > so that's what i did. i also raised the tank temperature to around 83 (it was > high 70's). > > thanks for any help. > > tsuh yang chen, nyc > > ------------------------------------------------------------------------- > This is the apistogramma mailing list, apisto@majordomo.pobox.com. > For instructions on how to subscribe or unsubscribe or get help, > email apisto-request@majordomo.pobox.com. > Search http://altavista.digital.com for "Apistogramma Mailing List Archives"! ------------------------------------------------------------------------- This is the apistogramma mailing list, apisto@majordomo.pobox.com. For instructions on how to subscribe or unsubscribe or get help, email apisto-request@majordomo.pobox.com. Search http://altavista.digital.com for "Apistogramma Mailing List Archives"!