The 2HP pump would be the only one running through the filter. The other 1 HP pumps would be returned directly to the water features. The water for the water features would still be filtered because it flows into the pool.

From what I understand, sheer descent requires its own filter. There's a post on here somewhere discussing that issue.

Here's a link below to sdkath's pool build. There's some detailed pictures of the equipment pad. It also uses a 3 pump system.

Here is a link that might be useful: San Diego Sunshine Poolbuild -- Thread 2

Thanks tsunami. I checked out the link to the SD pool. Pretty humbling. Makes mine look like a kids blowup pool. Anyway. If I'm going to run the spa isolated, don't I need some sort of filter? I'm planning on bleeding some spillover from the pool system that will keep it clorinated, but what if I get some dirt in it? I don't want to have to get my vacuum out if that happens. What about a small cartridge filter that won't restrict the flow too much? Thanks, Bruce

You can plumb the pool & spa to have either separate systems or a shared system. Mine shares the heater and filter but uses a separate pump for the jets. While the spa heats up, I cannot filter the pool but it takes less than an hour to heat up the spa and we usually don't use the spa for very long periods of time. The jets are independent so I can run those any time and it isn't necessary to have a separate filter for that.

I have seen completely separate systems where the spa has it's own heater, filter and pumps. It really comes down to cost and what you want to do with it.

A shared system is less expensive but you cannot filter the pool while heating/filtering the spa. Most of the time it is not necessary to do both at the same time but if you have the money, why not. A small filter doesn't cost too much but you may want to share the heater and chlorinator (e.g. swg).

Thanks for the info. I MAY want to run the waterfall at the same time as the spa so I think I'm going to get a small Pentair (CC75) filter for the spa that flows 75gpm. That's probably all my puni 4 jets will handle anyway. I'm definitely going to share the heater and swg. I rarely heat the pool so I'm planning on putting a manual valve in the system to provide for that. I bought the pumps a few years ago when I had the opportunity to get them cheap. Bought the Hayward stuff before I knew about this forum. 2 big mistakes.

OK. I'm giving up trying to design around my 2hp pump. Mas985, could you confirm that 2hp is too much for my 4 jets (1/2 in orafices). Thanks, Bruce

1/2" is fairly large for a jet so you will probably get pretty good flow rates. Assuming you have full rate pump (not a up rated), my guess is that head loss will be around 60 feet and total flow at 112 GPM. That is about 28 GPM per jet which is fairly high. You might check the specs on the jets to see what the recommendations are.

Thanks mas985. You're input on this forum is appreciated. I have purchased another 1hp max e glass ll (used). I will use 3 1hp. pumps. 1 for each of my waterfalls, and 1 to share the pool/spa. The plumbing and connection to the ps8 will be much easier. Thanks again. Bruce

Did you check on the flow rates for the spa jets? I wouldn't want you to be disappointed with the strength of a 1 HP pump. It should be enough but you might want to double check.

Thanks again. My jets are nothing more that 1 in. pipes with 1/2 in orafices in them. No threads. The orafices are set back in the 1in. pipes anywhere from 10 - 15 in. I was running a 2hp. 25yr. old pump and was ok with the flow. I have run them with the 1hp. when I was clearing an obstruction and they seemed fine. If I run the 2hp. then I would probably have to run the one of the waterfalls at the same time as I only have 2 eyeballs for return that share a 2in pipe. With the 3 pumps I can run any water feature and the pool/spa whenever I want. They're all independent. And I won't be running the 2hp. for my normal filtration cycle which will save me some juice.