What is the proper HP pump for a Sand Filter

[oldman]

I searched but I can not or did not find yet an answer to my question. I have a pentair sandfilter TA 35/35D sand filter that pumps 35 GPM hooked up to a Hayward Power Flow Matrix 3/4 HP which pumps 80 GPM. Is this diffrence in GPM going to cause me a problem? I have used this system for the past few years with no problem.

This year I hooked up one of those solar heaters from Game. I had to put a 6'foot hose from the filter to the solar heater and then use my 6' foot hose to the return outlet valve.

Also, before I hooked up the solar heater I tried adding DE to the sand filter, the day after the psi went up near 19 psi from 8 psi before puting in the DE. So I backwashed and psi went back to 8 then I add a 1/2 cup of DE and put on the solar heater and today I have 13 1/2 psi. Water looks great.

My question is. Is the 3/4 HP at 80 GPM to much for the sand filter that only pushes 35 GPM and cause me to lose filtering?

Thanks in advance for any advice. And is there some chart that matchs sand filters with the proper HP from a pump?

 

[JasonLion]

Sand filters usually still work when you run too much water through them, but they don't filter nearly as well as if you run less water through them. Over time a sand filter being used with an oversized pump will tend to get channeled, which means it will let debris through and not really filter at all, until the sand bed is resettled.

Another thing to keep in mind is that the pump doesn't necessarily put out it's rated GPM number. GPM varies with the length of your hoses and what else is attached to the plumbing system. When there is a rated GPM number it normally assumes a large filter, short hoses, and nothing else connected to the system. With the solar thing in the system the actual GPM will be lower.

By the by, those little tiny solar heaters really don't do very much. The amount of heat you get is proportional to the size of the panel. A small panel can't provide much heat no matter how well designed it is.

Another thing to be aware of is that the first time you add DE to a sand filter it will tend to suddenly start catching debris that it has never caught before, which can cause the pressure to go up fairly quickly.

 

[Bama Rambler]

First off, I get that you're probably pumping about 50 gpm through that pump. While that's still a lot for that filter, it should be fine. It could cause the sand to channel and pass debris through it but if it's been running for some time you're probably fine. When you do need to replace it I'd go with at least a TA-60 or 80.

 

[oldman]

That makes me feel better. Thanks guys for the quick reply. I have been spending hours looking at former post to that answer. Learned a lot of other things in the mean time. Great Site.