Choosing correct pool filter

[kamiyu910]

We recently bought a house with a 15,000 gallon pool and spa with a water slide. We've been having issues with it since we got it and are not impressed with the people who owned it previously. The pump they installed is a Whisperflo high performance 2HP pump and the filter has a design flow rate (gpm) of 120-150, which seems really overkill with a 15,000 gallon pool.
The filter housing just cracked up the side so we need to replace it, and I'm wondering what the best course of action would be. Would it be more beneficial to just replace the pump with a smaller system, or should I figure out a filter to go with our pump? I know little to nothing about choosing filters and pumps. I've attached pictures of what we have currently.
Thanks in advance!

 

[mas985]

Welcome to the forum!

That looks to be a cartridge filter and with cartridge filters, bigger is always better so if it wasn't broken, I would say that is a good size to have.

But to make recommendations, we really need to know a lot more about your setup. Please follow these instructions to fill out your signature with your equipment and pool setup.

http://www.troublefreepool.com/content/115-read-before-you-post

Please list all water features as well: Waterfall, Spa (# jets), scuppers, etc.

 

[JamesW]

Since you're in California, your electrical costs are probably high. Going to a variable speed pump is likely to be a good choice. You might even get a rebate from your electrical supplier. What are your electrical rates?

 

[kamiyu910]

We have solar now to help offset the cost, so we're paying about 15 cents per kwh currently, I believe.

I don't know everything about the pool, but I put in my signature everything I could think of.

 

[mas985]

So with spa jets, you don't want a smaller pump or risk weak jets but you could save some money with a two speed pump. Given you already have a 2 HP Whisperflo pump, a less expensive option would be to just swap the motor with a two speed motor. Cheaper than an entirely new pump and you don't need to change the plumbing (just the motor and seal).

The extra cost of a VS would probably take a long time to pay off vs a two speed motor. At $0.15/kwh, I estimate that break even with a two speed motor vs a VS pump is about 115 months (~10 years) which is close to the lifetime of the pump so you may not end up better off economically with the VS. A rebate would shorten the time some so something to look into.

Also, since you have high flow rates going through the filter with the spa, you are better off sticking with the same filter size you have now.

Is this something you would do yourself or hire someone to do?