Hey there,

With something as small as that, I wouldnt even bother with a filter. I would just change the water daily. Plus a filter isnt really going to be removing much of the amonia in the water, mostly just physical debri.

-Chris
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Currently in the US Navy so I have sold off my collection. But over the years I have had dozens of turtles, fish, geckos, and other lizards. Cant wait to get back in the hobby once im out though!