School swimming continuously around island?

[Bill Smith]

Hey all:

I have a nightstand space I want to use, and I was thinking of setting up something narrow and tall, with a high density of schooling fish.

I have always wanted to achieve that effect where you have a dense school of fish swimming continuously around an island in the center of the tank, with the fish all constantly traveling in one direction.

Has anyone gotten this to work? Is it something about the current? Proportional size of the island? Quantity of fish? Does the type of fish matter? I'm thinking rummy nose tetras, but CPDs or cardinal tetras would be amazing if they could be persuaded to school like that.

My working surface area is about 16"x12". A cylindrical tank will work if the fish swim this way, because the magnifying effect will be minimized by fish being closer to the tank walls.

Yes, it can take over 200 lbs., and yes, I will secure it with earthquake straps to prevent top-heavy tipping. Yes, my wife thinks I'm nuts, but bless her, she supports my hobby. 🙂

I'm also inspired by @Cory's bubbling "deep sea vents" in the 800 gallon, so I want my island to be bubbling.

How would you attack such a project?

Thank you!

[Alesha]

I have absolutely no advice for you,  but I can't wait to see what everyone suggests. And what you come up with.  Thinking about a smaller bedroom tank myself,  so watching closely. 👍☺️

[KBOzzie59]

There is this but you gonna need a bigger nightstand.

 

 

[Bill Smith]

I've spent some time in research, and there's not a lot of info out here!

1. The first thing I learned was the difference between schooling and shoaling. Shoaling is just fish hanging out together, but schooling is more about the fish moving in the same direction when their numbers are big enough. Not all shoalers are schoolers. Learned that from Rachel O'Leary.

2. Schooling behavior seems to come out when the numbers are big enough.

3. Water flow does not seem to be a big factor.

So it looks like I will need to find fish that are known for their tight schooling. Rummy nose tetras are a good example, but this being a smaller tank, I'm tempted to consider ember tetras, as I've never kept them before.
 

[Streetwise]

I really enjoy tetras. Ember Tetras have been great tank mates with Neocaridina in my 7.5. They are a bit timid. I recently got a dozen Bloodfin Tetras, and they are very active and swim together all the time.

[Mr. Ed's Aquatics]

I have a couple 55 hexagonal tanks and had one setup very close to what you're describing. I used large river rocks and wood to make the center island. I put the intake in the middle of the back painted section with the return facing forward on the left side of the back and a circulation pump facing backwards on the right. Kinda like a triangle, worked well and created a counter clockwise constant flow. Schooling fish worked great and they would all swim against the current and look like they were hovering. Or all turn slightly and the whole school would shift. I liked the look and it was an interesting tank to watch. 

Only thing I didn't care for was that it was kinda plain. Never found a center piece fish that liked the setup. 

[Bill Smith]

Okay, so I'm going to try it. But I ended up going with something a lot smaller than I originally intended:

This is a 5 gallon Fluval Chi, with several mods I've made over the last few days.

The plants and platies are temporary. After I make a real centerpiece island (bonsai-inspired tree with Anubias), I'm going to do something totally crazy and ill-advised. I'm going to try to fill this with enough ember tetras to see if I can get the directional schooling going in one direction. Maybe dozens of them. Maybe more.

I recognize this is crazy advanced level stuff and that I'll be changing water every couple days and checking parameters constantly. And having a larger tank ready as a backup. Nobody tell the fish police!

Watch the Journals forum for one of my over-detailed threads about the setup and mods!

EDIT: Here it is.

Edited September 3, 2020 by Bill Smith