To DE or not DE? That is the question.

[St8kout]

I just discovered a packet of documents left by the previous homeowner, among which are all the pool equipment manuals for the house I just bought.

Everyone I asked, from the pool guy to the realtor told me I had a DE filter, but no where in the Triton Mytilus FMY manual does it mention using DE. Then I just read PoolDoc's sticky above about NOT using DE with a cartridge filter. So why did everyone tell me I had a DE filter? I've even seen the pool guy put DE into the skimmer on two different occasions.

I was going to ask about some grayish-white sediment I keep seeing at the bottom of the pool, but now I'm wondering if it might be the DE that was added. I had been trying to stir it up with the sweeper so the filter could remove it but it's still there the next day after the water is cleared.

It's always something.....

[PoolDoc]

Everyone I asked, from the pool guy to the realtor told me I had a DE filter, but no where in the Triton Mytilus FMY manual does it mention using DE. Then I just read PoolDoc's sticky above about NOT using DE with a cartridge filter. So why did everyone tell me I had a DE filter?
I was going to ask about some grayish-white sediment I keep seeing at the bottom of the pool, but now I'm wondering if it might be the DE that was added.

Did someone HERE tell you it was a DE filter?

The gray sediment is probably DE, if people have been adding DE. You definitely need to clean your filter; you probably need a new cartridge. Try to get a Pentair OEM, or a genuine Unicel or Filbur cartridge.

[PoolDoc]

http://www.unicelfilters.com/pdf/replacement_guide.pdf, page 46:

Mytilus FMY 150 150 7-7/8" 33-3/8" 17-4980 C-7679 4 oz
Note: Product can also be replaced with one C-7699 and one C-7678.

Unicel C-7679 Replacement Filter Cartridge for 150 Gpm Pac-fab @ Amazon

Don't buy, till you've verified cartridge dimensions. You'll get best performance and life if you buy TWO and cycle them periodically. Filter cleaning guide here:
http://www.poolforum.com/pf2/showthread.php?18044

[St8kout]

No, nobody here to told me they used DE. It was the pool guy, both realtors (mine and the seller's) and a few other people. I didn't know any better so I took their word for it. I was going to buy some DE soon too. I did kind of wonder why my filters didn't look like the ones on youtube when I was looking up on how to service them.

I saw that the Unicels are almost half an inch larger in diameter so I opened and looked inside the housing and there's plenty of clearance. I ordered a set from Amazon.

[PoolDoc]

Sounds like you're getting on the right track.