Permanent Residents For A 20 Gallon Hexagon?

[onidrase]

I've been using a hexagon tank as a quarantine tank of sorts as I've been adding new fish into my 36 and 55. But now that both tanks are just about fully stocked, and I'm on my last batch of new fish, I'm thinking of turning it into a full blown community tank rather than a temporary residents for potentially sick new fish, and then buying a small 10 or 15 gallon standard tank which can be stored easily for sick fish.

Now, I'm not expert on the tall tanks, but the dimensions of each "panel" of glass is 9 and a half inches long and the tank itself is 18 inches tall, and from panel to panel is about 16 inches.

I'll be getting black sand substrate, and will also most likely be getting a submersible heater and biowheel filter(the current heater I have is hang on back with a C Clamp attachment to the tank, and the filter is so old the brand name is worn off, and the plastic is actually turning a rotten yellow color, they both work, but they're kinda clunky and confusing. The filter is also more noisy than my other two tanks combined )

Decorations will be a hard one, given the small footprint. probably a few long plastic plants and a small cave or two.

Suggestions are appreciated on this tank, what I'm looking for is 1 school or shoal of fish, (hopefully 6 to 8) some cory catfish if at all possible, some oto's is possible, and a centerpiece fish of sorts. I'm not very knowledgable on small fish, as I've been keeping larger ones since I've started the hobby on my own, which is why I got more tanks to accommodate that.

Take note, I'm really not a fan of cardinals, neons, or livebearers, but I'm willing to give them another go. I had them all the time as a little kid, and they lost their flavor after 5 or 6 years.

Thanks in advance, guys

 

[wroberson]

The calculator I used or the numbers I used came up with 35 gallons. That's like 30 inches of fish. I don't know small schooling fish. However, there are many 4 inch fish the school. I was 1st thinking a King Better or the Dragon scale betta would be a cool centerpiece fish, then I did the math.

School: Electric Blue German Rams (I'd like 3 myself)
Centerpiece: 1 Pair Millennium Rainbow fish.

 

[onidrase]

The calculator I used or the numbers I used came up with 35 gallons. That's like 30 inches of fish. I don't know small schooling fish. However, there are many 4 inch fish the school. I was 1st thinking a King Better or the Dragon scale betta would be a cool centerpiece fish, then I did the math.

School: Electric Blue German Rams (I'd like 3 myself)
Centerpiece: 1 Pair Millennium Rainbow fish.

Uhh. No. Really not.

rams aren't schooling fish. And my tank is too small for them.

Rainbowfish are schoolers that are very active, definitely not for a tall tank. You don't keep them in "pairs," you keep rams in pairs.

The 30 inch rule is not a universal rule. It's just a minor guideline to avoid over stocking somewhat. And it doesn't even fit this tank, why would you do calculations to estimate how much water a tank can hold when I already told you how much water the tank holds? You might have been right if this was a rectangular tank, but it's not. It's a hexagon. It's shaped a bit differently

 

[DrRob]

Interesting problem these tanks present. Not much swimming room by way of floor area, but plenty of water.

Pygmy cories are lovely, as are the sparkling gouramis. Both could get a sensible shoal going, the pygmies particularly might look great.

The little chilli rasboras look lovely too.