I have a problem with my tank. A few days ago we had some electrical upgrades done and our tank was off for several hours longer than they'd anticipated.
I used a battery operated airstone to try and keep the filter going but I don't think it worked because Ammonia tested at 1.0 the next day. I've been doing daily water changes of one third and using Prime each time. Ammonia now reads 0.5.
My Cories are just lying on the tank floor, grouped up together. Admittedly they do show more life at night which is what I'd expect, but they're normally far more lively in the day than this. I know they're very sensitive to Ammonia and I'm worried about them. Can anyone tell me what else I can do? Any help would be gratefully received.
The thing you need to do is monitor ammonia and nitrite levels at least once a day and do enough water changes to keep ammonia below 0.25 and nitrite below 0.50 until the cycle re-establishes. Right now, that means a 50% change. Every time you change water, add enough Prime to treat the whole tank at double the normal dose which should help detoxify the small amount of ammonia and/or nitrite remaining. Adding an airstone, or positioning the filter outlet to create extra surface disturbance will also help.