Sand or Cartridge Filter for New Pool

[Watermom]

Another vote for sand. Also one more tidbit ----- when you initially fill your filter with sand, do a quick backwash before putting it on filter.

[Toybuilder]

Thanks Watermom. Out of curiosity, do you add DE into your filter also? Does everyone? What does that do to the warranty of the filter? Do I dare tell my builder?

[CarlD]

1) You don't have to use DE
2) You only use a little bit, just enough to raise PSI 1lb.That usually means 1/4 to 3/4 of a cup.
3) DE shouldn't hurt your grass, but it will kill many kinds of bugs.
4) It won't affect your pool's warranty, but may affect the filter warranty, but shouldn't as it won't damage the filter.
5) I would not tell the builder. Not his business.

[Watermom]

I do sometimes add DE but not routinely. You can read more about adding DE to a sand filter in the following thread:>

http://pool9.net/de-test/

I cannot imagine how adding DE would affect the filter negatively. Filters are made to trap debris. Basically, DE is just debris that is caught by a sand filter just as any other debris would be.

[Toybuilder]

Thanks everyone for your very helpful input. Went ahead and told the builder to go with sand. However, I noticed that he will be installing the largest filter available for a Pentair Triton II, the TR-140C. which will need 925lbs of sand (really??). The pump will be a Pentair Intelliflo VS pump and will have an attached spa. The pool capacity will be ~16k gallons. He explained that we needed the larger filter because it’s the only one rated to flow the amount of water that we need for the spa to function properly. The spa only holds ~850 gallons. Does this sound right? I think I’m going to need more than 1/3 of a cup of D.E.

I will be anxious to try D.E. but I think I'm going to hold off and see what it looks like without it. I will add the skimmer sock immediately once we're up and running.

[FormerBromineUser]

Yes, you can say the brands and models. Give as much info as you can to the equipment guys on the forum before you commit.

[Toybuilder]

Yes, you can say the brands and models. Give as much info as you can to the equipment guys on the forum before you commit.

Point taken. Will edit my previous post.

[CarlD]

While 925# seems like a lot, you ARE filtering a spa, which I presume requires a much higher flow rate for all the jets if it's a single pump--I'm guessing as I know nothing about spas. But he's 100% correct that the filter MUST have a greater capacity than the pump. With filter that large you may WELL see fantastic performance that makes DE unnecessary. You can always try it, and if you don't like it or you put in too much, you simply backwash and VOILA! it's gone!

Be absolutely certain he installs surge protection for your VS pump, not just GFCI. They are very sensitive to surges and lightning, having electronic circuit boards. While they do perform better than a 2-speed pump, they are more sensitive because of the electronics.

These days, with all the electronic appliances, surge protection is everywhere. We have to have it on our washer and dryer, even though the dryer is gas, because they are electronic. We have lost too many coffee makers till I put a surge protector on the latest one! We even have a fridge and range that have them on them (gas stove, electronic controls)!

[BigDave]

Rinse is a setting on most multiport valves. Your builder may be installing the full flow valve as flow for the spa appears to be the factor driving filter and pump selection. I don't know if the full flow valve option has a rinse position. There is an MPV option for that filter but it would probably restrict flow.

I think your builder is offering a nice filter and you'll be happy with the water quality. Don't worry about the half-ton of sand, you'll never have to replace it (unless you use Baquacil or cellulose DE substitute).

[Toybuilder]

While 925# seems like a lot, you ARE filtering a spa, which I presume requires a much higher flow rate for all the jets if it's a single pump--I'm guessing as I know nothing about spas. But he's 100% correct that the filter MUST have a greater capacity than the pump. With filter that large you may WELL see fantastic performance that makes DE unnecessary. You can always try it, and if you don't like it or you put in too much, you simply backwash and VOILA! it's gone!

Be absolutely certain he installs surge protection for your VS pump, not just GFCI. They are very sensitive to surges and lightning, having electronic circuit boards. While they do perform better than a 2-speed pump, they are more sensitive because of the electronics.

These days, with all the electronic appliances, surge protection is everywhere. We have to have it on our washer and dryer, even though the dryer is gas, because they are electronic. We have lost too many coffee makers till I put a surge protector on the latest one! We even have a fridge and range that have them on them (gas stove, electronic controls)!

Whew! Thanks CarlD. This builder said he has over 28 years of experience, and for a moment, I thought were being taken.

I will try D.E., just because I’m more curious than anything, but will wait a few weeks after startup to see how it looks without it.

As for surge protection, the builder actually recommended it. We do get some severe lightning storms over the summer months here in the Denver metro area so better safe than sorry. He just installed one on a pool that was struck 3 times before the owner got fed up (I would have been fed up after the first time). He’s telling us to go ahead and purchase the surge protect on our own as he would have to mark it up if he were to purchase it, $200 vs less than $100 from an online store I found. I take savings anytime.

He’s also having us purchase the SWCG which I have more questions on that. Should I start a new post in SWCG? I’m looking at the Hayward Goldline but not sure which one? Size?

Thanks again for all your help, and for everyone else’s help for that matter. You’ve made me feel a lot better about the filter…and the builder. I will be posting several more questions around the forum so please keep the good information flowing. I can use all the help I can get.