Cray, stiphodon/sicyopterus and danio questions

Regarding the crays: I wouldn't recommend keeping a marmorkrebs in a 10 gallon set up as they reproduce parthogenically so the tank would be overrun with just one bunch of babies.

You could keep one of the larger crayfish but most of them do eat plants and/or fish. If you have a tank of livebearers I would recommend one Procambarus alleni or P. clarki to help keep the fish population under control. You could even go with looking at some of the Cherax species of crays as they are less likely to mow down the plants but you'd have to go carefully as some get very, very large--as in tankbusting large. The good thing about the Cherax sp of crays is that they tend to have more vivid coloration and would really pop as a centerpiece cray. There are far to many crayfish to start naming good selections but if you find some that you think would be nice--I'd be happy to help you with the particulars.
 
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