Dwarf Rasbora in a ten gallon?

🐠 October TOTM Starts Now! 🐠
FishForums.net Tank of the Month!
Click here to enter!


New Member
Apr 2, 2018
Reaction score
Hey, can anyone tell me how many dwarf/pygmy Rasbora I can put in a ten gallon? Considering on average most are .75inches full grown with a few reaching an 1inch I was thinking about 10-12. Six I believe is the minimum and the bigger the school the more comfortable they are, so I want the max that will be healthy in my tank.

Thanks in advance!
How long is a 10 gallon tank, 2 foot?
If so you could have 15-20 small rasboras assuming you do a 50% water change each week and monitor water quality. If you have other fishes in the tank, then reduce the number of rasboras.

These numbers are for an aquarium with an established filter.
I agree, but if it is a new tank make sure you do a fishless cycle (see: http://www.fishforums.net/index.php?/topic/421488-cycling-your-new-fresh-water-tank-read-this-first) and / or plant it heavily.

Also go to seriouslyfish.com and check on the requirements of your chosen species to make sure that your water is suitable fo both pH and hardness. If in doubt post your water parameters on here and let someone advise on a suitable species. The important numbers are pH, GH and KH which should be available on your water company's website. Note that for GH and KH we will also need to know th unit of measurement.

Once everything else checks out I agree that 15-20 would be fine but you would need at least a 50% water change every week.
I’m currently cycling a ten gallon for Boraras maculatus or dwarf rasbora. I am shooting for a pH below 6 and my water is a hardness of 3GH AND 1KH. It has oak leaves, oak branches, 3 pieces of driftwood and a Malaysian wood with a brown sand substrate. The plants are duckweed, salvania, and frogbit for floating plants and a moss. I want a Blackwater setup so I’m letting the tannins in as much as possible and little light getting into the tank to mimic its natural environment. I’m stocking 12 Borarus maculatus and 12 Sundadanio axelrodi. They are similar size to each other so I think you could get 24 if you want a species only setup provided the tank is cycled and has a sponge filter. They will not do well with a strong current from a HOB filter and keep up the maintenance. Good luck.
Assuming by "dwarf/pygmy rasbora" you mean one of the species in the genus Boraras, then yes, a group of 10-12 in a planted 10g (floating plants are essential, lower plants up to you) is fine. And you are correct, these species need more in the group than just a half dozen.

I had a group of these in my 10g, along with a similar-sized group of pygmy cories, with no filter, just plants, for a year. It was an experiment of sorts, but the point here is that the fish thrived in this environment. Weekly water changes of 50-60% of the tank of course.
Hey guys, thanks for the replies. My tank is cycled and ready to go, just wanted to make sure my school size would be okay
. I am shooting for a pH below 6 It has oak leaves, oak branches, 3 pieces of driftwood and a Malaysian wood

What is the PH of your tap water? The leaves and wood wont lower the ph by much if at all.
What is the PH of your tap water? The leaves and wood wont lower the ph by much if at all.

Out of the tap it is 7.4 and now the tank is 6 or lower. My main tank is 6.4 so I started by using half freshwater half tank water and the pH went from 6.8 to 6 or less in just a week. The KH is 1dh so there is no buffering.

Most reactions


Members online