Question
I have a tank with four 1.5" Shubunkins, which I've had for one month. There are no other fish. It is a glass-bottom tank with no substrate (for easy cleaning), and has many floating plants for them to hide in. The tank is equipped with just an AquaClear filter and an auto-feeder.
Whenever someone approaches the tank, all of the fish run into the plants, and won't come out. They only swim around when they don't see anyone nearby. I've never seen any other fish behave this way, except maybe catfish.
Why might the fish always be scared? Is that a sign there is something wrong with the tank?
Answer
I had this same issue with my Danios, and it confused me because Danios are usually all about coming up and trying to get your attention when they see you.
then I realized, the autofeeder was the problem. they weren't associating the big scary noisy thing outside the tank (me) with a sudden abundance of delicious foods, but Instinct was telling them that anything that big is probably dangerous. I'm pretty sure goldfish have similar instincts.
Maybe I'm off base in my theory, but i started feeding them by hand again and in no time they were back at the front of the tank being the little beggars that they are, whenever you walk by. I still use my autofeeder for a daphnia culture that I've had going for a while.
My advice is to try feeding them by hand for a week or so, see how it goes! As others here have said, it never hurts to check your water parameters, either.
Answered By - dan