How big will A Cory cat get? I wish I couuld add 2 to my tank but I'm pretty full alredy.
Some Cories very in size but usally they are 3 to 4 inches in length
The smallest cories get an inch and they are Pygmy cories. The largest I have seen was an emrald cory and it was 3inches
They wouldn't take up the same swim space, since you don't have bottom-dwellers, so I actually think 3 or 4 pygmy cories would work okay. But I would be concerned about filtration. I'm no expert. but I know ideally you should have 200 gph flow rate with a HOB filter on a 20g tank. Yours is 150 gph. I can't imagine that pgymy cories would have a huge bioload, but I don't know if your filter would be able to handle more fish.
Maybe someone else can chime in.
I'm going to plug in your parameters on aqadvisor and see what it says about your filtration.
edit: I put in 4 pygmy cories. This is the result:
Warning: At least 5 x Cherry Barb are recommended in a group.
Warning: Tiger Barb is too aggressive to co-exist with Cherry Barb.
Recommended temperature range: 23 - 24 C. [Display in Farenheit]
Recommended pH range: 6 - 7.8.
Recommended hardness range: 5 - 15 dH.
Warning: You should add more aquarium filtration capacity.
Your aquarium filtration capacity for above selected species is 88%. [What's this?]
Recommended water change schedule: 32% per week.
Your aquarium stocking level is 105%.
Yeah I've been using that same site.
depends on the type, bronchis cories can get 4-5 inches, most cories get around 3.5, and pygmy's get to around 1-1.5 as was already mentioned. also, cories prefer groups of three or more, they would probably be a bit lonely with just two.
Stepped up my filter today. Got the 200 penguin.
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