Following a water change, I have a single tank that had a major fish kill. I need a little help understanding. I did my weekly water change in both 55-gal tanks and my 10 gal tank. I have used "Ultimate" water conditioner (1 ml / gal) for years. On the last tank, I ran out of "Ultimate" and had just purchased "Big Al's Multi-Purpose Aquarium Water Conditioner" which I was planning to try (save a buck). So the last 8 gal of make-up water, I used the 'Big Al's". I went about my other chores around the house and noticed at the night time feeding, the fish (African cichlids - yellow labs and blue johannies) were shy and did not frenzy feed like usual. I had to go out of town the next morning and before leaving noticed EXTREME distress. The larger fish (5-6 inchers) where on sides, barely moving and gasping at the surface and multiple smaller fish were dead. All other tanks are fine.
I suspect the new conditioner. I thought the Big Al's was the similar chemical used to remove Chlorine and neutralize Chloramine just like the Ultimate. There is a "Contradiction" listed on the Ultimate which says "do not use with permangante-based or chlorite-based treatments". I thought those were used specifically for things like copper and lead chelating and chlorite was used as a santizier, so I really don't think that Big Al's falls into that category.
I am at a loss. Was able to rescue the larger fish (saved) by moving to the other 55 g. (The pictus catfish are not happy in that tank.) I thought I would come back from out of town to an complete kill in the tank, but those that survived the first 24 hours, have made it.
I changed a total of about 18 gals in the 55 gal. The first 10 gal treated with Ultimate and the last 8 gal treated with Big Al's. Nothing else is changed. I do not suspect bucket contamination since my other tanks are fine. No other water params are outside what my tanks usually run.
I suspect the new conditioner. I thought the Big Al's was the similar chemical used to remove Chlorine and neutralize Chloramine just like the Ultimate. There is a "Contradiction" listed on the Ultimate which says "do not use with permangante-based or chlorite-based treatments". I thought those were used specifically for things like copper and lead chelating and chlorite was used as a santizier, so I really don't think that Big Al's falls into that category.
I am at a loss. Was able to rescue the larger fish (saved) by moving to the other 55 g. (The pictus catfish are not happy in that tank.) I thought I would come back from out of town to an complete kill in the tank, but those that survived the first 24 hours, have made it.
I changed a total of about 18 gals in the 55 gal. The first 10 gal treated with Ultimate and the last 8 gal treated with Big Al's. Nothing else is changed. I do not suspect bucket contamination since my other tanks are fine. No other water params are outside what my tanks usually run.