wanted to put one blue cray in my 20 gallon but its a 20 gallon high will that be a problem?
20 gallon long is recommended. A 20 high doesn't have a big enough footprint. Is there any way you can upgrade?
unfortunately i don't have the money to upgrade
Then I wouldn't recommend getting a blue crayfish. I believe you can do 2-3 Dwarf Mexican Crayfish, though.
they will be good in a 20 high?
Yeah, their minimum is a 1og gallon, which has the same footprint as your tank. Make sure to do your research though.
True 20 gallon long is much better for crays but if you are talking about blue crayfish the blue color morph of Louisiana crawdaddy, either p alleni or p claekii they are rather tiny(5 inch eye to tail) even full grown male will look like it is in a mansion 24 by 12 by 16. In fact the 16 inch of empty water column probably will bother most people so much at some point that they usually get some fish and find them gone overnight. I do agree with penguine tho, you should definitely get a few dwar cray, and you can get some nice fish too.
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