Bioload

[Lira]

I have a 40 gal breeder tank for a betta sorority with other tank mates. Mix of silk and live plants. Decent amount of hiding places and swimming space. Plan to slowly introduce all fish, in the order listed. Does this sound like a doable bioload? Thanks!
1. 8 harlequin rasboras
2. 3 kuhli loaches
3. 5 panda cory catfish
4. 6 female bettas

 

[Essjay]

I would increase the numbers of kuhli loaches (you'll never see them with only 3; they need a big group for confidence) and cories; but think seriously about the female bettas. Many members have had a 'peaceful' sorority them woken up to a bloodbath.

All these fish are soft water fish so if you have hard water you need to either rethink or 'soften' the water by mixing it with pure water such as reverse osmosis water.
And bear in mind that the loaches and cories need sand on the bottom of the tank - I don't know if you have sand or gravel but cories need to sift the substrate for food which they can't do with gravel, and kuhlis like to bury themselves.


Provided you do a fishless cycle, you can add most of the fish at the same time. If you are dead set on the bettas, add all the other fish first, then leave them to settle before adding the bettas.

 

[Lira]

Thank you for your thoughtful response. Very helpful. Might it be better to swap the sorority for one male betta? Is it more likely that females would attack each other than a male betta attack benign fish, like rasboras or loaches?

 

[Fishmanic]

A single male Betta should be in his own 5 gallon or larger tank. You could add maybe a single Nerite snail.

 

[Essjay]

Male bettas have variable temperaments. Some will attack anything that moves; some are so laid back they get bullied to death. But even laid back bettas have been known to snap several months down the line and go on a killing spree.

As Fishmanic said, male bettas are best kept alone, and nerite snails are just about the only tank mate they leave alone - though I once had a betta which flared and postured at a nerite snail when it was on the tank walls.
Many people do keep a group of female bettas but usually just the bettas in the tank, no other fish. Even then they have a potential for aggression.


You could always have a group (1 male, two or three female) honey gouramis instead of the bettas. All gouramis have attitude, but honeys are at the least aggressive end of the spectrum.

 

[Deleted member 149562]

I currently have a male Betta that I took on from a now deceased neighbour. I have owned Betta in the past and all have had a varied temperment as @Essjay rightly says.

The one I have now is a male short finned little brute. He goes for me when I am doing maintenance...flares and nips. He lives in a 29 gallon aquarium and with it being so large, I am trying him out with a juvenile BN that is one that was born in my other aquarium about 7 months ago

The BN is more than capable of holding her own defensively. But even after almost 2 weeks, he still chases her, flares at her and tries to nip her. He is not impressed at all. I shall give them another week or two and if he won't calm down, the BN will return to her original aquarium.

Betta are hard wired to be aggressive...maybe not today or tomorrow but they will often turn, sometimes with warnings such as curling around food or snapping at tankmates that maybe pass too close or making tankmates too fearful even to come out at mealtimes. It builds up over time...a male Betta is a stunning fish but with that beauty often hides an extreme nasty streak. They aren't called Siamese Fighting Fish for no reason.

 

[GaryE]

Kuhli loaches and Corys aren't a good combination, as they compete for food. That's not bioload, but behaviour.

 

[sharkweek178]

Kuhli loaches and Corys aren't a good combination, as they compete for food. That's not bioload, but behaviour.

Plus, neither listed amount is a full shoal.

 

[Lira]

Thank you. This is information I really need.

 

[sharkweek178]

Thank you. This is information I really need.

Another thing to consider. Panda corys like a high water flow. Bettas aren't suited for a lot of flow. There are other corydoras that are good with low flow, like Sterbais.

 

[Lira]

Plus, neither listed amount is a full shoal.

How many kuhli loaches in a full shoal, approx?

 

[sharkweek178]

How many kuhli loaches in a full shoal, approx?

I'll say this with the disclaimer that I've never kept kuhlis myself. Seriously Fish says 5 or 6. @Byron who has forgotten more about fish than I'll ever know has cited studies that shoaling fish should be in groups of at least 10. I believe it. In nature, fish school in the hundreds or thousands. So I'm inclined to think that a higher number than 6 is needed.
The thing you have to understand about shoaling and schooling is that it's a natural defense behavior. It's how fish protect themselves against predators. When fish aren't in sufficient numbers, they're living in fear of being eaten. And it shows in their stress level and behaviors.