"Travis Jordan" wrote in message
...
Brandon wrote:
I am having a heck of a time finding an answer. I have a 13,500
gallon pebble tec freeform pool. I.A 763 surface area of 435square
feet. 82 foot perimeter.
I am going to replace the Jacuzzi cartridge filter with a sand filter(
Hayward, Pentair,sta-rite...other suggestions appreciated), filled
with one of the Zeotype medias.
BUT I cant figure out what SIZE filter to buy..
18/24/30?
Is there somewhere to determine this online? I have been told three
different things by different dealers.

http://www.pested.msu.edu/BullSlideN...E2621chap8.pdf

The above link is pretty good. However, you need to know a little more. You
can calculate what your water flow SHOULD be to turn the water through the
filter in X number of hours. However, your pump may produce way more or way
less flow than what you calculate. The sand filter may also have more head
pressure than the cartridges you have now. This will reduce the flow rate
from the pump you're using now.

The good news is your pool is rather small, so a 40 GPM pump and a small
filter is probably sufficient. My pool has an undersize filter for the pump
that is installed. I've bought the next larger size bacause it will better
handle the 50 GPM rate my pump provides. The filter I had before was rated
at 40 GPM.

My triton filter has its suggested flow rate as part of the model number
(TR-40, TR-50, ...). You'll need to visit the website for the filter you
want to buy and see what size is required for the water flow rate you have.
May also want to find the specifications of the pump you have now and see
what flow it does with your existing head pressure, and a head pressure 10
PSI higher than what you have now.

--
Mark
Kent, WA