Defective Aquarium

This is more of an investigative post as I'm just curious as to why this happened. I have since disassembled the tank due to frustration.

I have 3 display tanks, two of which have puffers that I grow snails for. I now grow snails in my betta tank. But I used to grow snails in a designated 20 gallon long tank.

At one point, we decided to put it in a cabinet (kind of like where you would store pots and pans) and take it off the counter. After that, every snail died. I had about 100 ramshorn snails. Since my wife was the one who actually moved the tank, I figured she was too rough and sloshed them around or got some dish soap or something in the tank. So I cleaned the tank by rinsing it with hot water for a while. I was super thorough. I went to the store and got more snails, put them in, and they all died again. After that, I decided to try mystery snails since I figured they grow to "optimal size" faster than ramshorn. They didn't die right away, but never ate or come out of their shell. I took them back to the store. I tried ramshorn 1 more time and they all died again...

I cleaned out the tank again and used it for a quarantine tank when I got new danios. They were fine for a month and are all living in my main tank healthily and happily. I disassembled the tank after that. Since then, I started growing snails in my betta's tank. This is successful and I have a huge colony for my puffers.

During all this, the tank was cycled. Nitrate was always under 10 ppm. It was a barebottom tank with a couple plastic decorations, but not much. I even tested for copper and had none.

The snails were healthy and breeding before I moved the tank. The danios I bought and quarentined for a month lived in there fine. But any snails I put into the tank after moving died. My wife was 'positive' she didn't get any foreign substance in the tank. I don't know how true that is, but I rinsed the tank for about 15 minutes, dried it completely, and rinsed it again.

Any idea why or what happened? Again, I disassembled the tank/filter and threw them away. I'm just completely confused as to why this happened and am wondering why.

 

Any way the cabinet had ever been sprayed with insecticide?

 

Any way the cabinet had ever been sprayed with insecticide?

Ooh, that's a good question. Folks do spray cabinets for pests. I couldn't come up with a scenario to explain what OP described.

 

Hmm that's a possibility... It is an apartment so they may have done that before we moved in. But the cabinet it was in was quite large and wasn't perfectly sealed off. And it didn't affect the danios, just the snails.

 

Danios are bulletproof.

 

Lol so are ramshorn snails!

Before I started keeping puffers and needing snails, I tried LITERALLY everything to get rid of them. Boiling the substrate, bleaching stuff I buy before using it, copper based algae control. Nothing worked against those things.

Now that I actually need them they die on me. Good thing it's easy to start a new colony and my puffers enjoy frozen food. They don't love anything as much ash their snails though.