Wow, this is next on my list after I get the algae I'm fighting now. But I wanted to ask if it's ok to leave the sand filter connected to the system but bypassed? My sand filter is large and kind of stuck back in a hard place to get to. Thanks
Yes it can be left in place. Most people don't move it but some need to because it's in a structure that they don't want to flood with water or would be difficult to clean up the junk that comes out of the filter during the process so they chose to take it out of the system and do the deep cleaning in a different location.
Having recently deep cleaned my filter, something to be aware of is the NEXT time you backwash be prepared for some very dirty water. While I likely should have deep cleaned longer than I did, I suspect the deep cleaning process loosened up crud that my deep cleaning did not wash out from the sand filter and/or refreshed sand just cleans a whole lot better!
I should note that in my case, I could NOT detach the sand filter from the system because the installation of my sand filter left only an inch or so on each side of the filter (thus preventing me from moving the filter without first emptying a good amount of the sand.
Whatever the explanation, just be ready! I'd like to add my thanks to Smykowski too - your video was reassuring and a great resource!