What's coming out of my return? (under water videos)

Baker25

Well-known member
Jul 1, 2018
59
Roscoe, IL
After manually vacuuming, I turn off the pump to unseat the skimmer box lid. Then I kick the pump on, and this is what I see. If I backwash after I vacuuming, then I don't see this. I do find what I believe is sediment on the pool floor shortly after the pump kicks on. Links for videos showing the sediment are also posted. Not sure if the issues are related.

Return video:
Dirt video #1:
Dirt video #2:
 

Texas Splash

Mod Squad
TFP Expert
LifeTime Supporter
I would start with the following questions to get more info so we can help:
- How long has it been since you deep cleaned the filter?
- Can you post a full set of test results?
- What pressures (before cleaning and after) are you seeing on the filter pressure gauge
- Any unusual FC demand in 24 hrs?

In video 1 it almost seems like dirt residue blowing back because you didn't backwash. Granted you might expect everything to stay in the sand, but if it's overloaded or the sand is compacted/channeled, the filter may not be able to retain all of the dirt you vacuumed, so the backwash helps to blow it out.

Videos 2 & 3 however almost look like small organic spots that brush easily away which is why I asked about test results.
 

Baker25

Well-known member
Jul 1, 2018
59
Roscoe, IL
I would start with the following questions to get more info so we can help:
- How long has it been since you deep cleaned the filter?
- Can you post a full set of test results?
- What pressures (before cleaning and after) are you seeing on the filter pressure gauge
- Any unusual FC demand in 24 hrs?

In video 1 it almost seems like dirt residue blowing back because you didn't backwash. Granted you might expect everything to stay in the sand, but if it's overloaded or the sand is compacted/channeled, the filter may not be able to retain all of the dirt you vacuumed, so the backwash helps to blow it out.

Videos 2 & 3 however almost look like small organic spots that brush easily away which is why I asked about test results.
The sand is brand new, as of 1.5 months ago if that. I've had this stuff in the bottom of my pool since I got the pool last year. I'm seeing just shy of 20 psi, and after a backwash it might go down a few ticks. Weirdly enough, when the pump is off, I still show some pressure on the gauge. When I put the new sand in, that's what the starting pressure was as well. I just finished a SLAM so my FC is about 12, CC is 0, CYA is 30, PH is about 7.6.

I've posted a few other times about this stuff but never had the videos. I recently put a sock over the return and even after a full day of the pump running and after a vacuuming, I had nothing in the bottom of my pool. Which is why I think whatever is coming out my return is ending up on the bottom of the pool. With zero wind, within an hour of turning the pump on, I have sediment on the pool floor. Should I just start backwashing every time I vacuum?
 

wireform

Silver Supporter
In The Industry
Aug 15, 2017
482
Spring Valley, NY
Not sure about the dirt issue but if the Gauge doesn't rest at 0 psi when the pump is off, it's time for a NEW Gauge. There's no way to know your real pressure this way.
 

Baker25

Well-known member
Jul 1, 2018
59
Roscoe, IL
Just to confirm .... was it specifically pool sand (#20 silica)? For the SLAM, I suppose you ensured you passed all 3 criteria correct?
Yup, it was sand that I seed suggested on this site several times. And yes I passed all 3 tests. Like I said, these little spots of sediment have been showing up since the beginning. I manually vacuum every day and it ends up right back on the pool floor
 

cj133

Well-known member
May 6, 2018
214
NJ
Did you inspect all of the laterals before dumping the sand in and was the filter half full +- of water before you added the sand?
 

Baker25

Well-known member
Jul 1, 2018
59
Roscoe, IL
Did you inspect all of the laterals before dumping the sand in and was the filter half full +- of water before you added the sand?
Yes and yes. I actually replaced the lateral thinking it was letting stuff back in the pool. The old one looked fine but I changed it out anyways. New one was obviously fine as well.
 

Baker25

Well-known member
Jul 1, 2018
59
Roscoe, IL
Backwashes after vacuuming today and water was clear on pump start up. No sediment in pool a few hours later. So if the sand is new, what else could be causing dirt to be allowed back in the pool?
 

Baker25

Well-known member
Jul 1, 2018
59
Roscoe, IL
You can try this trick:
I will have to look into this!

So far I have backwashed every time I vacuum and the water is crystal clear coming from the return on start up and no sediment on the pool floor. I know this is not how it's supposed to be. Is there a physical issue with the filter somewhere, or this just a thing?
 

duraleigh

Admin
Mod Squad
TFP Expert
Platinum Supporter
LifeTime Supporter
In The Industry
Apr 1, 2007
32,853
Sebring, Florida
If I backwash after I vacuuming, then I don't see this
Next time you vacuum, turn off the pump and go to the "rinse" position for 1-2 minutes. Turn off the pump again, Then go back to the "filter" position on your mpv and start the pump. I think that will eliminate that dirt coming from your returns.