Maintenance of cartridge end caps and DE, Pentair

[susa]

Pentair Clean & Clear cartridge filters contain these black end cap inserts on both sides of the cartridge (top,bottom).

When these cartridges are cleaned, is it necessary to remove these 2 end caps?

Also read for the first time this blurb from the owners manual:

When the cartridge element filter is used on new pools and after cleaning the elements, introduce into the system .5 pounds
of diatomaceous earth per every 100 square feet of filter area, (a one-pound coffee can equals .5 pounds of diatomaceous
earth). Mix the diatomite with water and pour it into the skimmer after the pump is primed and the system is operating. This
will enhance the filtration of your water.

 

[257WbyMag]

I will remove the caps on the top but I'll leave the bottom ones in place as I haven't seen any reason to remove them as of yet.

That's the first that I have heard of adding DE to a cart filter system. I personally wouldn't do it, but that's just me.

 

[frustratedpoolmom]

I have heard of certain manufacturers/models recommending DE for their system, but it's not a general recommendation for all carts and in fact can ruin some. If your owners manual recommends it any harm that might arise should be covered under warranty if the system is new. If this isn't a new one I wouldn't bother.