8 return lines for a pool?

[prop]

i am in mexico and had a pool built 15 years ago 15x5x 1.5 meters and it has been working fine until last year when it developed a leak.i figured out the leak was in the return lines and disconnected the main return from the pump and ran a new line above ground to the far end of the pool and it works fine.i just can`t figure out why there are 8 return lines, 3 on each side and 1 at each end.the drain and skimmer are at the end closest to the pump house and the new return at the opposite end.i have a pool in the states that is bigger then this one and only has 2 returns at the opposite end of the drain and skimmer.i never really paid much attention to the build years ago but i wonder why 8 return lines.

[Teapot]

My response is, don't worry about the 8 returns on a pool that size. Obviously the placement of them matters but better you have them to circulate the water and push debris towards the skimmers.
My worry would be the idiot Pool Builder who built you an even bigger pool with only 2 returns, what an idiot! Bet you have more maintenance cleaning etc.

[prop]

i have had the pool with 2 returns for 30 years without any problems. i open , close, maintain and clean it myself no problems. it`s 20 x 50 ft ,9 ft deep and i replaced the liner about 10 years ago. all i use is chlorine baking soda and copper sulfate and it`s crystal clear.as far as the pool in mexico i have been using the one return for a year now with no problems ,it just seems like 8 returns are overkill.

[Teapot]

Its human nature to defend the point but if you get the water circulating really well then the dirt is kept on the move and will eventually make it into a skimmer where it can be filtered out. Others buy robots and fancy hoovers to clean their pools but the clear water is actually a settlement tank, as the cleaning takes place the becomes hazy and the dirt that is disturbed gradually settles back to the floor until the next time its cleaned.
A really clean pool has no dirt to stir up.
I used computational fluid design software to explore how best to place the skimmers and returns to keep the dirt moving to filter it and 6 returns would be about the norm a bigger pool could go to 8.
I use a min of 2 returns per skimmer. The reason is to lower the pressure in the system as that pressure is friction and wasted energy and electricity.
That also means sizing the filtration at an efficiency level in regard to the flow of the pump.
The biggest failure in pool systems is the flow needs to at the correct level for best filtration but much higher flow for backwashing filters. Single speed systems may function but are not optimised for energy saving or best performance, why bother if it works? My pool has save me over £3000 in the 10 years since being optimised, thats tons of CO2 saved the water clarity is that of drinking water, amd maintenance is absolutely minimal. I sold the pool robot and use a pool blaster max occasionally.
Pool filtration only works when its running and my system runs 24 hours a day on less electricity than a std pool would in just 2 hours.
Some people are they tell me happy running their pools for 8-10 hours per day and spending a couple of hours with some kind of vacuum removing the detritus that has sunk to the floor, thats fine but I would rather not and I prefer the savings in time and money. I know my pool uses only a tiny bit of electricity so saving tons of CO2.