My DE grids are acting like water balloons - can't even lift them out of the filter tank. Any particular reason?

anthonypool89

Well-known member
Aug 26, 2016
301
Berks County, PA
I seem to recall running into this during last season with at least one set of grids (I have two). Today I opened the pool and did an initial charge of DE. This is the first time I'm using one of the new glycerin-filled gauges (love it since it's calibrated to 1/2 lb. increments). What was really weird was an initial starting pressure of 15 (typically 10-12 with all my old gauges). If 15 is accurate, I'm fine with that except that after about 2 hours - with the pressure at 20, I get a "no flow" indication on the heater. Bummer! I figured that with a starting pressure of 15 I'd be good till about 25. So then, upon opening the tank is when I discovered the water-filled grids. I had to clean them as best as possible with them still in the tank (granted there was aLOT of debris on there since the pool looked like the usual stinky swamp once the cover was off). Once able to lift them out, I cleaned them off with a high pressure nozzle - as I usually do - but then noticed that the water just sloshes around inside the grids no matter which way you turn them. The bottoms of the grids (turned upright or sideways - makes no difference) are puffy - about an inch thick or so with water. Turning them different ways simply moves the water around inside. I loosened the nut on the side until all 10 grids were loose and. that seemed to help the water drain out. Is there not a good seal at the center of each grid? Nut too tight? I mean, obviously water passes through these things but I can't recall in years past ever having this trouble with the water retention and being too heavy to lift. It's frustrating since what is usually a 40-minute job turns into twice as long for not being able to remove and work easily with the grids.

Any thoughts? So - to finish the saga - after hosing off, replacing grids, recharging, I noticed an operating pressure of 17. As it was getting late, I added some clarifier (baquacil pool) and set the timer to go off in an hour. By the time it shut off, pressure was up to 18.5 (after about 45 minutes). I dread to think of what tomorrow might bring. I know there can be several filter changes when getting the pool started, but I don't understand the unusually high starting pressure. Or are the grids just getting clogged with debris even before I have a change to start putting the DE in the skimmer? Thanks...
 

njswimguy

Member
May 20, 2020
5
Marlton, NJ
How long has it been since you've acid washed the DE grids? It may be that they are beyond what can be cleaned with a hose and they are gummed up. When I ran Baquacil I would have them acid washed every 1-2 years.
 

anthonypool89

Well-known member
Aug 26, 2016
301
Berks County, PA
Just acid-cleaned both sets at the end of last season - haven't been used since then until today. I acid-wash several times a season, which is why I bought an extra set of grids. That way I can be cleaning one set without taking the pool out of service.