Deep Cleaned Sand Filter - Painful lesson learned

[EdKuhn]

My sand filter was installed in 2014. I was prepared to replace the sand but after reading here I discovered a cleaning would do basically the same! So I opened the filter yesterday and discovered a) the diffuser and air tube were pushed to the side, not vertical like they are supposed to be and b) I was about 100#s short on sand!

Today I deep cleaned the filter and added two bags of sand. The backwash was extremely dirty but it cleared after a bit, same with the rinse. I thought I had isolated everything but I didn't....I should have taken out the SWCG so that I had a gap between the pump and the returns... painful lesson learned. Brown stuff shot into the pool for what seemed an eternity but was probably about 15 seconds.

Now my previously sparkling, just-off-a-SLAM pool is slightly cloudy. I don't have a way to measure FC/CC since I am out of reagent but I do have a Taylor CL kit that will let me know if it's above 5ppm at least. And getting ready to go on vacation in less than 36 hours...I dumped 2 gal of 10% bleach in - based on yesterdays' readings that should get me back to SLAM levels. man oh man!

 

[zea3]

You should be able to vacuum up any sand that was dumped in the pool. Anytime you add sand, you need to backwash and rinse until clear, so that any sand that got in the standpipe is flushed out. Did you backwash and rinse after the deep clean or did you skip the deep clean and just add sand?

On the bright side this should clear up pretty quick!

 

[EdKuhn]

You should be able to vacuum up any sand that was dumped in the pool. Anytime you add sand, you need to backwash and rinse until clear, so that any sand that got in the standpipe is flushed out. Did you backwash and rinse after the deep clean or did you skip the deep clean and just add sand?

On the bright side this should clear up pretty quick!

I deep cleaned, then added sand, and backwashed and rinsed before I started things up again. I ran both until clear. I think I forced some gunky water into the laterals while deep cleaning, with the hose maybe? I saw a little coming out of one of the returns, before I turned the pump back on, as I was walking to turn of the water hose. Hmm maybe that explains why I have been losing sand each backwash? A broken lateral? Or maybe the sand loss was because the diffuser was pushed way down, not vertical? Pool seems to be ok now, not crystal like it was before but getting back for sure. I'm sure to be vacuuming tomorrow but thats ok, as long as I can relax when I'm gone.

Edit I had the multi-valve set on "closed" while I was doing the deep clean.

 

[zea3]

You probably do have a broken lateral. After vacation you can empty the sand out and replace the broken lateral. Yay something to look forward to after vacation!

 

[EdKuhn]

You probably do have a broken lateral. After vacation you can empty the sand out and replace the broken lateral. Yay something to look forward to after vacation!

Of course after I just replaced about 1/3 of the sand in the filter....

 

[zea3]

When you take the sand out put it on a tarp or in some buckets and you can reuse the sand. When you check the laterals also check the standpipe for hairline cracks that may open up when the filter is under pressure.

 

[EdKuhn]

When you take the sand out put it on a tarp or in some buckets and you can reuse the sand. When you check the laterals also check the standpipe for hairline cracks that may open up when the filter is under pressure.

Good idea. Great way to get the sand super clean too!