How often to backwash DE?

modog

LifeTime Supporter
Aug 4, 2009
68
Any suggestions? Pool Builder says every 4-6 weeks. If my pump pressure hasn't increased, do I need to backwash?
 

Bama Rambler

Mod Squad
TFP Expert
LifeTime Supporter
Jun 22, 2009
23,036
SouthWest Alabama
If your pressure hasn't increased and you're fairly certain that your gauge is good you don't need to backwash. There are people here that only backwash once a season.
 

Melt In The Sun

TFP Expert
LifeTime Supporter
Oct 29, 2009
3,899
Tucson, AZ
Yep, watch your gauge. Some people only backwash once a season, but others have to backwash every week or so, even without any algae problems. It just depends on the quantity and type of debris you get in your pool, and your filter size; your filter is pretty big, so I wouldn't expect you to need much backwashing.
 

zea3

Mod Squad
TFP Expert
LifeTime Supporter
Jul 10, 2009
11,064
Houston, Texas
You can see if you have pressure rise, and decreased flow from the returns. They usually occur together but if your pressure gauge is defective you may not see a pressure rise when you have decreased flow. If everything is going well then I would leave it alone.

Just fyi, if you have a true backwash setting on the filter, it will not release all of the dirty DE. You will recharge the DE after you back wash and over time the DE can build up on the grids. This will require that you open up the filter and hose off the old DE off. If you notice the time between backwashes getting shorter and shorter then DE build up is likely the problem.
 

modog

LifeTime Supporter
Aug 4, 2009
68
Thanks for all the responses. I learn something with every post! When I do backwash, they gave me this cup from a DE bag and told me to add 10 of them (apprx 10 lbs) of DE. Is there any guideline to how much I should add?
 

Bama Rambler

Mod Squad
TFP Expert
LifeTime Supporter
Jun 22, 2009
23,036
SouthWest Alabama
After normal backwashing you should add about 2/3rds to 3/4ths the initial charge amount. So if your initial recommended charge is 10lbs then you'd add 6 to 8lbs after a backwash.
 

zea3

Mod Squad
TFP Expert
LifeTime Supporter
Jul 10, 2009
11,064
Houston, Texas
Keep in mind it is 10 lbs by volume not by weight. The old method of measuring DE was to use a 1 lb coffee can. They now make DE scoops with the same volume as a 1lb coffee can. For a full charge add 10 scoops of DE, for a partial charge add 6-7 scoops.
 

waste

TFP Expert
LifeTime Supporter
Mar 29, 2007
4,160
Coastalish 'down easter'
I'd be willing to bet that the scoop they gave you is .75 lbs.

10 of them would = 7.5 lbs which would be right for a 60 sq ft Hayward filter, however- the Jandy DEV 60 takes 6 lbs clean :eek: I suggest checking the manual or the outside of the tank, there should be a label saying how much DE to add to a clean filter :wink:

You might find some helpful info here
 

Other Threads of Interest