Agh Dead Molly

[gazzab06]

about 1 hour ago i put a new air stone in my tank,went back to it ater half hour and one of my mollys was floating around the bottom of my tank ,dead as a door nail !!

i checked him over and there was no marks or what looked like disease. i just did a water check - nitrate-50,nitrite-1,gh/dt/th-21*d,carbon hardness-3*d,ph-7.6.im due a water change 2moro,so are them stasts ok?

i washed my hands/arms before i put them in the tank but think i might have had aftershave on my arms still. this would pollute my water?..............i guess ill have more dead in the morning


gaz


forgot to mention i have fed mty other fish and they all seem fine.


gaz

 

[nmonks]

What killed the molly was the nitrite; 1.0 mg/l nitrite is deadly to most fish, but mollies are exceptionally sensitive when maintained in freshwater conditions. (Interestingly, they're bulletproof in brackish and saltwater tanks, and have been used to mature new marine aquaria for decades.)

Your airstone surely hasn't caused the nitrite spike -- something else like overfeeding, overstocking, or clumsy maintenance of your filter may have triggered this. How old is the tank? Goes without saying you never EVER cycle a new freshwater aquarium with mollies. Mollies need a stable, mature tank (I'd say 3 months old, at least).

In any event, if all you're keeping are mollies and other livebearers, adding some salt, even tonic salt, at 6-9 g/l will make all the difference. Marine salt mix is better, but tonic salt will do, the key thing being the NaCl detoxifies the nitrite ion significantly, and for those fish that tolerate/like salt, this is a tried and trusted approach. Long term of course you need to establish why your nitrite level sky rocketed.

Hope your fish recover, Neale

(I happen to like mollies, hence answering this question; I'm one of those people who usually ignores questions written in "text message speak"!)