In the leadup to the recent betta show, to try and help get some extra growth out of my young HMs in order to make minimum size requirements I was feeding 3 times a day and giving all my fish in my 2 Aqua One Barracks a 100% waterchange either every day or every second day for just over 4 weeks.
In the 5 day period of getting everything ready for the show, then having the show, I didn't touch any of the fish or water except to give daily feeds - I figured that I could slip back into weekly waterchanges and they'd be fine. On day 3 (Friday) I removed the bettas I was entering, gave them a waterchange put them into their beanies. After that, the rest didn't get a look in. They were fed Friday night, then I spent the weekend up at the show and didn't come home until Sunday afternoon.
When I got home and looked into the barracks, I was devestated to find 2 fish dead in the barracks, 1 crispy female who had jumped out and several not looking so good - my steel boy who previously had problems with rot had holes in all his fins and my new black orchid HMPK pair were looking half dead laying on the floor of the barracks.
I instantly gave all fish a waterchange and most slowly picked up over the next 24 hours. My new HMPK pair have not improved and I keep expecting the worst every time I look up at them.
I should have tested the water, but a combination of lack of sleep and sheer panic had me forget that basic step - I had to get those fish into clean water STAT.
What I am thinking (and this is only a theory) is that the constant water changes over the previous month upset the balance or even killed off the good bacteria in the sump filter material and that when I left the barracks to it's own devices for 5 days, it went into a cycle and the fish died from an ammonia spike. I am so annoyed with myself. I guess it could have been worse - at least I have my show stock.
What are your thoughts? Could I be right about the barracks cycling?