I started off with max 6 (2 x males + 4 x females) in a 4ft x 4ft x 3ft high (so they are pretty much inbred) but shows no deformities... (pond is heated in winter by a 4kW geyser element on a timer switch).... Also did this to guppies and platies, with same results.how big is the pond? I thought about doing something similar, but thought they'd die come winter.
I've been ding a trial stocking of a couple of mollies and some green swords in a 150 gallon stock tank. So far I like what I'm seeing in growth but the winters here get too harsh for fish to survive it. I will be pulling them out in the next month or so and will know better how things worked out. If I like the results, next year it will get a part of my endler colony so it can really explode with growth.