scampbell, are you absolutely, positively sure that there are no fish in these ponds? Any remaining fish could wreck your plans, so ensuring that these ponds are void of any pre-existing fish would be my first task.
As far as a net? Are the ponds rectangular like commercial hatchery ponds, or round like recreational ponds? Lots more variables in net size and cost if the ponds are round with varying depths and sizes.
