Well, if it makes your son feel better, flowing at 2-2.5 gpm will do a pretty fair job of giving you some depth. That is close to 3,000 per day. As long as your evaporation is less than 3,000 gallons per day, the spring will keep filling it. It won't fill it up real fast, but he will still be able to swim in it and you could stock FHM and maybe BG fingerlings in another few weeks. That is as long as you don't need to drain it to seal the spring and put in your piers. As far as what to seal it with, I am ignorant on that count so I will wait and see what other people have to say.
