Newbie trying to understand circulation issue

[Bill Kruse]

Bought a house with an inground pool that hasn’t been opened in at least 5 years. Had a pro come and open, and have done a bunch of work to clear out 50 gallons of crud from the pool. I have used lots of good info from this website/forum to get me clear! It is looking good now but have a strange circulation issue.

When on filter mode (sand filter btw) only 2 of the three returns have any flow. In recirculate mode all 3 work, but the originally non-flowing one (return #3) only has low flow. When I cover one of the the returns nearest that one (return #2) then return #3 flow increases to a higher flow, but not full flow. Also When going to recirc, all 3 start spitting out small debris. I am thinking that the higher pressure in recirc (not flowing through the filter) is partially clearing some clog in the line for return #3.

Anyone have any ideas what might be going on and what to investigate to try to fix.?

 

[Texas Splash]

Welcome to TFP! Sounds like one supply line feeds all 3 return jets, so the last one will be the runt of the little and might get less flow. You might also still have some residual algae which is clogging the filter and restricting water flow. Do you have a proper test kit? Either a TF-100 or Taylor K-2006C? If not, that needs to be step one. If you do, please post a full set of results. If the water has any haziness to it at all, I'm guessing it's still fighting algae. To kill algae we follow the SLAM Process using one of those test kits I noted above. Very important. Algae is a chemical issue and no amount of backwashing will resolve it. So read those links and let us know if you have any questions.

Pool Care Basics Archives

Your one-stop shop for all things TFP to include: ABCs of Water Chemistry, Recommended Chemicals/Levels, Test Kits, Troubleshooting, and much more!

www.troublefreepool.com

 

[BassPlayingDude]

It could also be that your pump is undersized for the amount of "head" present in your piping, or as compared to your filter size, or that perhaps your old pump is getting ready to give up the ghost. Deep cleaning your filter might help it flow better as well. Touch the side of your pump housing when it is running. Is it too hot to comfortably touch? If it is, that's a good sign that it is on the struggle bus.

 

[Bill Kruse]

Welcome to TFP! Sounds like one supply line feeds all 3 return jets, so the last one will be the runt of the little and might get less flow. You might also still have some residual algae which is clogging the filter and restricting water flow. Do you have a proper test kit? Either a TF-100 or Taylor K-2006C? If not, that needs to be step one. If you do, please post a full set of results. If the water has any haziness to it at all, I'm guessing it's still fighting algae. To kill algae we follow the SLAM Process using one of those test kits I noted above. Very important. Algae is a chemical issue and no amount of backwashing will resolve it. So read those links and let us know if you have any questions.

Pool Care Basics Archives

Your one-stop shop for all things TFP to include: ABCs of Water Chemistry, Recommended Chemicals/Levels, Test Kits, Troubleshooting, and much more!

www.troublefreepool.com

TXsplash.....thanks for the reply. I had ordered the Taylor K2006C. I came from Amazon yesterday And am now vowing to never buy or use test strips again! Threw them in the trash. Nowhere close, except for pH.

Here are my results for today:

75 degrees
7.5 pH

So far so good.....

Free Cl2. 15.6
Combined. .8
TA. 275
CH 700
CYA 100

Saturation .85

Water was clear and blue on Monday. My son had some friends over.....by 9pm water was cloudy. Has cleared some since, but still cloudy.

My first step to slam is to drain some water and refill.......CYA is so high because I was duped by the test strips (said I was at 10 and I raised to 30) or so I thought.

I have also read that adjusting TA down is usually the first step to water balancing, but I am thinking that drain and refill might help that too?

 

[Bill Kruse]

TXsplash.....thanks for the reply. I had ordered the Taylor K2006C. I came from Amazon yesterday And am now vowing to never buy or use test strips again! Threw them in the trash. Nowhere close, except for pH.

Here are my results for today:

75 degrees
7.5 pH

So far so good.....

Free Cl2. 15.6
Combined. .8
TA. 275
CH 700
CYA 100

Saturation .85

Water was clear and blue on Monday. My son had some friends over.....by 9pm water was cloudy. Has cleared some since, but still cloudy.

My first step to slam is to drain some water and refill.......CYA is so high because I was duped by the test strips (said I was at 10 and I raised to 30) or so I thought.

I have also read that adjusting TA down is usually the first step to water balancing, but I am thinking that drain and refill might help that too?

However...the more I have run the system, the flow from return 3 is increasing, so I think it was just algae/scale filled.

 

[Texas Splash]

You have the right thinking in exchanging some water to lower the CYA. That has to be first, then you can properly balance the FC either for a SLAM Process to remove algae or regular days. But do that exchange first. We'll help you work on the TA later. Order of events would be as follows:
1 - Water change to lower CYA; verify CYA; hopefully around 50 or so.
2 - If water is cloudy, prepare for a SLAM Process by adjusting the pH to about 7.2
3 - Increase the FC to the proper FC SLAM level noted on the FC/CYA Levels.
4 - All other chemical levels will be tended to after the SLAM.

If after the water exchange the water appears clear and you aren't sure about starting a SLAM Process, you can run an Overnight Chlorine Loss Test to confirm. Hope that helps. Good job testing!

 

[Texas Splash]

For future FC testing, do the following:

10 ml water sample size with ONE generous scoop of powder (should go Barbie pink). Mix and add drops until clear and divide result in half. Example: 20 drops equals an FC of 10.

 

[Rancho Cost-a-Lotta]

Bill,

To save on reagents, use a 10 mL sample for the FC test. Use one scoop of powder and multiply the number of drops by .5 (or just divide by 2) to calculate result. You should be able to get a full season of FC tests out of the kit.

What size sample did you use for the TA test. If you used a 25 mL sample, multiply drops by 10. Your TA result would be 110 ppm.

Good luck!

Edit...I guess Texas Flash beat me to it...

 

[Bill Kruse]

Bill,

To save on reagents, use a 10 mL sample for the FC test. Use one scoop of powder and multiply the number of drops by .5 (or just divide by 2) to calculate result. You should be able to get a full season of FC tests out of the kit.

What size sample did you use for the TA test. If you used a 25 mL sample, multiply drops by 10. Your TA result would be 110 ppm.

Good luck!

Edit...I guess Texas Flash beat me to it...

Rancho,

Thanks. I was using the 10ml sample for TA, so 275 is right!