3" fish for 20 gallon tank

Kribs are very pretty and IME breed very easily which is kinda fun. the only complaint I have about mine is they stay in their hole 90% of the time yest was the first time in weeks I saw the male at all and it was with a bunch of babies lol mine are also pretty agressive, they killed off all my neons and an endler I put in there to give it a try and attack my pearl gourami anytime it goes below the bottom 25% of the tank or so

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I would say no to the kribs if it's a 20g...they get NASTY, and this is from personal experience. Apistos are nice. I'm ordering a pair for my 30 tall today.
 
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