I have read a ton, but I haven't really seen my specific situation come up, so here goes.
Background first: Last year, we bought an 18x48 Intex inflatable. I was TFPC from day 1 and we never had any major issue. Minor issues were all side effects of the small pump and filter - overloaded pollen, cloudy water from lots of sunscreen, lots of bugs on surface, etc. But pool health was always good, and we never had chlorine demand problems. I cleaned the filter 2-4 times/week, vacuumed 1-2 times/week, and skimmed the surface daily.
This year, right away, we upgraded to the 2800 gph sand filter. The difference is already remarkable. I thought we had a nice sparkly pool last year, but this year our sparkles are RAINBOW sparkles. It's really amazing. Mesmerizing, in fact. But I'm having a few new issues and I'm not sure if I actually have a problem, or if this is a new normal.
The sand was purchased at a pool store - Mystic II angular filter sand. It's very white, and while I'm sure I didn't backwash or rinse long enough, I don't think I've had any sand go back into the pool. So that's one problem I don't have.
What I do have is a lot of fine silty brown dust? pollen? dirt? on the pool floor. We're suffocating under crazy pollen right now in New England, and I live near lots of farms. Either the silt on the bottom is dirt I didn't wash out of my filter, or it's pollen and farm dust. We've been in a couple times, and it just dissipates with turbulence. Currently, it's too cold to collect some and look at it under my daughter's microscope. I know I have to vacuum, brush, keep the pump running, keep a cover on, and possibly add DE to my filter. I had hoped it would just go away, but it's been 2 weeks and the dust is still there (with pump on 4 hours/day). My FC has not dropped below 4 ppm since opening (CYA currently targeted for 70), so I'm reasonably sure it's not algae (I never have CC when testing). My pressure gauge started around 8 psig and it's still there. I haven't backwashed since my initial startup. Am I correct that I just need to keep cleaning and the dust will probably get better when the pollen dies down or the sand gets a little dirtier? Am I missing something?
My next problem is the air in my prefilter when I vacuum. With the old pump, I was used to bleeding out the air in the filter whenever I saw bubbles at the return jet. If that didn't fix it, I knew it was time to clean the cartridge filter. With this new sand pump, I can't bleed air out, but it seems to take care of air on its own. But the new pump is so powerful, it creates a suction side vacuum whenever I hook anything up to the nozzle. I have an over the wall skimmer that kind of works, but I can only use it when I'm able to watch it - otherwise, it clogs or starts to float, or the nozzle strainer grid clogs and I have to detach the skimmer from the wall to clear the grid. If I have to watch it, I might as well just skim manually.
Vacuuming is equally trying. It's a cheap pool, so I picked up a cheap Intex vacuum - why mess with nonstandard connections if I don't have to? As soon as I connect the (fully primed and correctly submerged) vacuum, the prefilter floods with air and the water level drops to about halfway. Is that normal? Am I causing damage to the pump? Is there any way to fix it?
Frankly, I've about had it with that suction nozzle strainer grid. I'm ready to cut it right out and rely on the prefilter to catch the big stuff. Is that a good idea or a horrible idea? I did see a post recently where some others cut theirs.
Sorry for the novel. I have been reading, reading, reading, but I guess I let my problems pile up a bit. Thanks for any help you can offer!