So I pretty much nuked the secondary system in my fish room. The secondary system runs off of Kalk. The top off bucket was empty, so I put enough freshwater in the sump to turn off the auto top off and then poured water into the bucket, same as always. Typically, by the time the auto top off kicks on again, the kalk has settled in the bucket. For some reason, it dosed a lot of Kalk into that system. It was really murky but I've done something similar to this before and everything was ok. This morning, pretty much everything, including the fish, was dead. I even thought that maybe I should move everything to the main system last night but decided it would be ok. It was not ok.