Question Glass Catfish Behavior Question


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Quick glass catfish question:

Recently added three glass catfish to my established aquarium. Went to my local store and came across a tank full of them. Thought they looked awesome so, initially, I brought home one. The man who worked there told me "one will be just fine."

After doing subsequent research I found out these are schooling fish. Keeping one is basically just asking the thing to die of stress. Went back the next day & picked up two more. Ideally, I'd like to have five, but there just isn't room in my tank for that yet. Hours of research online said they won't be as out in the open with three, but three is fine as a minimum.

Long story short: The initial glass cat purchased (he only has one whisker so he's easy to distinguish) has become the life of the party. He started eating flakes the second day. While he'll occasionally school with the other two (well, the three of them hover together), he swims around by himself all the time. Not glass surfing. He'll swim up and chill underneath the filter for awhile, then he'll hover in the middle of the tank. If I come to the glass he'll follow me. He'll occasionally swim from one side, to the other, then back.

The other two stick together near one corner of the tank, sometimes swim around in front for awhile, then go inside the ship and hover. They're a little more active at night when the lights dI'm to a dark blue.

I've done a ton of additional readings on these fish. From what it sounds like ... the original catfish isn't acting right. These guys are supposed to be timid, stay together all the time, and hang out in low-light places & only come out at night. Is something wrong here? Should I be worried? As the three of them are in the tank longer together, will they start spending more time together?

One additional note on feeding: In the morning I provide flakes (which the original is now eating) and then the sinking shrimp pellets for other fish on the bottom. I've seen the other two shy glass cats come out during feeding time, but haven't visually seen them go up and take flakes. Will they pick at the shrimp pellets at the bottom? Should I be worried I haven't seen them take pellets? Is this something where, after a couple of days, they'll get hungry/acclimated/start eating?

The first two days I had the original cat, he didn't go up and take the pellets either. He started doing that Day 3. If the other two follow the same plan, they should eat tomorrow morning.

I think these guys are freaking awesome. Aside from my electric blue ram, they're my favorite fish in the tank. Really want to give them a happy life!

Background on tank: 40 gallon, community tank with only one semi-aggressive fish (rainbow shark) || Filtered my Marineland 200 & Fluval aquaclear 50 || bubble wall in back || 3 real plants and 2 fake ones (in process of converting to all real) || 2-piece shipwreck for coverage. Tank has been running ~10 months.

Below is a picture of the full tank, and then of the catfish just chilling in the middle. The other two catfish are hovering together inside the left portion of the shipwreck.



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Pennsylvania, USA
2 years
From what I understand about glass cats, they turn white/opaque when stressed, so if all your three fish are looking clear and (hopefully) eating in the next few days, they should be fine and happy. That being said, I have heard that glass cats with shortened or missing whiskers is a sign of a glass cat-specific disease, but if you're seeing him with one whisker completely healthy (as in, no white tip to it, and comes to a natural point) then I would not be worried about his one missing whisker.

I have a few pearl gouramis that took over a week to start taking food and not absolutely flip out any time someone walked in front of the tank, but once they got fully acclimated, they've been very social fish and will come right up front and center when I walk up to the tank. I imagine that your first one seems like the "life of the party" because you got him first and he acclimated before the others. Nothing to worry about! Hopefully the other two will soon join him and everyone will be happy.

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