This is an interesting subject and you raise a good question. I am pretty new so I would start with the load for a ten gallon. Then experiment with a load to a 15 check the water perameters after additional cycle time and the proceed from there. So since youll never have the full 38 gallons of space It seems like that may be over stocked but, I am just a newb.. However you will have a greater swimming surface than a 10.
I built a paludarium in a 29h I wouuld like to share with you.
If could change what I did on this project I would have used very large cork trunk pieces, all ephiytic plants, less or no baskets, and no cocos fiber.
Some plants didn't make and some have just taken off. http://www.dendroboard.com/phpBB2/vi...er=asc&start=0
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