Some of you will remember this pool from the old forum. It's a VERY large residential pool built at least 50 years ago. 77' X 27' and ranging from 3 and 1/2 to 11 feet deep. Best calc for volume is 85,000+- gallons. Dave S. and Kelly, you've gotten me to where I am right now on this project.

Todays dilemma is reducing the 2.5 inch return line to match return fittings through the shell. It seems most available eyeball type fittings are 1.5 inch f.i.p. The plan is to return about 125 gpm through 3 or 4 through the shell outlets. I've obtained a 2" fip fitting that has 1.5 threads inside it. That has a nice wide escutchen that would cover the giant hole I'll be core drilling through the 18" shell. Believe it or not, the pool seems to have been built entirely of fieldstone and then hand troweled concrete applied to the interior. It's really tough concrete and my guess is the drilling will be a heck of a struggle. I cut the skimmers relatively easily with an angle grinder and concrete blades. The question is whether the 2" is overkill. To get the 2" through the shell will require a 3" core bit, but 1.5 only a 2.375" bit. Since the return water is forced through 1" eyeballs anyway, would reducing the 2.5 inch return line to 1.5 inch shell penetrations make any difference in THD? I'm renting tools tomorrow. Please give me your thoughts.

Regards,

Josh