Chloramine

[Joel Wadleigh]

Hello fellow catfish growers. I live in Austin, Texas and I'm in the early stages of cycling my outdoor flood and drain aquaponic system in preparation for catfish and I've hit some snags.

I've been putting goldfish in the tank to increase the nitrogen levels and they've been dying very quickly. At first I thought it was maybe poor acclimation or extreme cold at night, but I've since learned that comet goldfish should do fine at 60 degrees F. I tested the chemistry of the water and found that pH, alkalinity, hardness, and ammonia were all fine, but chlorine was a little high. After looking into what is put in the tap water here, I learned that chloramine is the only disinfectant added. My tank has mostly tap water in it. I thought the chlorine in it would off-gas if I let it sit, but if it's chloramine, I think it's probably persisting since it is a much more stable compound in dilute solutions. My question is, how would you guys treat tap water to get rid of chloramine? I've heard that using sodium metabisulfite or potassium metabisulfite are good ways to remove chloramine, but I'm concerned about whatever sulfur products that might leave in the water. I've read superchlorination will break up the chloramine so it will off-gas, but putting a huge does of bleach in my system doesn't sound very pleasing, even if it is supposed to all off-gas. I've also read that boiling tap water for a while will remove chloramine, but that sounds expensive and time consuming.

Help!

- Joel from Austin

[TCLynx]

I like that description