I'm a long time pool owner and at my wits end trying to get my pool in shape!

[ImDudelin]

I have used the old pool math. It tells me to do what I have been doing for 35-40 years. I know my pool. Adjust ph, shock/slam with 3 gal chlorine. once was usually enough. Would last for 4 to 6 months before cleaning again.
All that changed 2-3 years ago. Started only lasting 2 months, then 1 month, then few weeks this year. Last, only 2 days! I can't backwash my filter. My system is too old for that. Must pull out manifold/grids by hand, clean with hose. Sweep pressure went down from 55 lbs to 0 the first night after cleaning. My pool was light green before last shock (had been very dark). The filter plugged up way way too fast. I can't clean it every other day. Can't do a slam with low water flow either, can I? BTW, now when I turn on the pool sweep pressure goes up to 65 + lb, in 5 minutes its dropping. in 15 its down to 40, or less.
I've been trying to figure what is going on, and getting worse, for two years I've now concluded that the DE filter has became plugged up with algae and/or calcium; when clean, plugs up again in few hours.
I was hoping someone at TFP would have experience/knowledge on cleaning grids with chlorine or acid. Will it work?

 

[reggiehammond]

Here's how to clean.

Cartridge Filter Use and Care - Further Reading

www.troublefreepool.com

Re: How to clean a cartridge filter

Re: How to clean a cartridge filter After 7 years, I've replaced my 4 cartridges in my filter (I could have gone longer, but the straps were starting to break and I figured I had a good run with these cartridges). The replacement cartridges for my Jandy CL340 were from Unicel® and they had...

www.troublefreepool.com

I'm confused by how you describe your sanitation - you'd add 3 gal of chlorine and then nothing further for 4-6 months?

As others have mentioned, your filter is likely plugging because your FC is killing organic material. The organic material (algae) is likely there because your FC is not being maintained per FC/CYA Levels.

 

[ImDudelin]

Here's how to clean.

Cartridge Filter Use and Care - Further Reading

www.troublefreepool.com

Re: How to clean a cartridge filter

Re: How to clean a cartridge filter After 7 years, I've replaced my 4 cartridges in my filter (I could have gone longer, but the straps were starting to break and I figured I had a good run with these cartridges). The replacement cartridges for my Jandy CL340 were from Unicel® and they had...

www.troublefreepool.com

I'm confused by how you describe your sanitation - you'd add 3 gal of chlorine and then nothing further for 4-6 months?

As others have mentioned, your filter is likely plugging because your FC is killing organic material. The organic material (algae) is likely there because your FC is not being maintained per FC/CYA Levels.

No, no. I wouldn't have to clean the filter. I just used tabs/liquid as needed, to keep the water in control. Tank/sweep pressure would be OK. Thanks for the link! I will check it out.

 

[ajw22]

Here's how to clean.

Cartridge Filter Use and Care - Further Reading

www.troublefreepool.com

Re: How to clean a cartridge filter

Re: How to clean a cartridge filter After 7 years, I've replaced my 4 cartridges in my filter (I could have gone longer, but the straps were starting to break and I figured I had a good run with these cartridges). The replacement cartridges for my Jandy CL340 were from Unicel® and they had...

www.troublefreepool.com

I'm confused by how you describe your sanitation - you'd add 3 gal of chlorine and then nothing further for 4-6 months?

As others have mentioned, your filter is likely plugging because your FC is killing organic material. The organic material (algae) is likely there because your FC is not being maintained per FC/CYA Levels.

Reggie, he has a DE filter...

DE Filter Use and Care - Further Reading

www.troublefreepool.com

 

[reggiehammond]

Reggie, he has a DE filter...

DE Filter Use and Care - Further Reading

www.troublefreepool.com

Ah - I thought he was asking how to clean the actual DE cartridge filters (if gunked up with oils, potions, etc), not how to clean a DE filter.

 

[ajw22]

The filter plugged up way way too fast. I can't clean it every other day. Can't do a slam with low water flow either, can I?

Let me try again.

Your DE filter is clogging up due to the algae. A DE filter works too well when you have a big algae problem.

I asked you before for picture for your equipment pad and filter.

Do you have an MPV with a RECIRCULATE setting or a slider valve?

With a DE filter you need to do the SLAM Process in phases.

First phase is kill the algae without filtering. That means removing the DE grids if you do not have the RECIRCULATE setting. Follow the SLAM Process maintaining SLAM level FC and brushing the pool.

Second phase is filtering once you see your FC drop has slowed down and you are home with available time to babysit your filter and backwash it every few hours when it clogs with algae.

When you get enough algae killed and filtered you can then finish up with SLAM level chlorine and filtering simultaneously.

It all works if you patiently follow our process step by step with no shortcuts.

 

[ajw22]

Ah - I thought he was asking how to clean the actual DE cartridge filters (if gunked up with oils, potions, etc), not how to clean a DE filter.

Nauitlus DE/48 uses grids to hold the DE.

Pentair has a different model DE filter that uses four cartridges instead of grids.

 

[Chuckiechan]

Just an idea....
Could he SLAM the pool, but leave the pump off or a day or two, mixing by brushing? Then when the SLAM seems to be effective, turn on the pump?
Also possibly adding some non copper algicide?

 

[ajw22]

Could he SLAM the pool, but leave the pump off or a day or two, mixing by brushing? Then when the SLAM seems to be effective, turn on the pump?

No, he needs the water circulating to deliver the chlorine to where the algae is hiding.

A still pool with no circulation will stratify.

Also possibly adding some non copper algicide?

Algaecide may prevent algae. Once algae is in the water it does nothing. Algaecide does not kill algae, chlorine does.

 

[ImDudelin]

Thursday, 25th. ajw - you asked for pics. I have no cell; used my 35mm. this am. Will try to attach below.
Cleaned filter again yesterday/Wednesday. Was going to try to soak the whole grid in TSP, but unable to find in CA except for phosphate free, which I've read won't work (at Walmart, on-line only). I attempted a spray bottle at about 7% muriatic acid all over and inside as best I could. That hasn't seemed to do any good.
Yesterday shocked w/3 gal 12.5%. Tank pressure 10 lb, before n' after DE. Sweep on to 55 lb, tank went up to 15 lb. Went out in early am, sweep was at zero. Tank to 17 lbs. Turned off for a minute. Sweep pressure back to 65+. I already know its going to drop down. A few minutes ago, sweep at about 30 Adjusted diverter valve up; raised rpm from 2600 to 2800 = sweep 55 lbs. Tank now at 20. Checked chlorine = 1.5; was dark yellow yesterday evening. PH was 7.2 CYA from 2 readings = 48 (=tricky test)
I know. Slam, slam, slam. I have bought 16 or 20 gals chlorine recently @$35 for 4 gal plus DE and acid. The algae, but mostly the 100+ heat is eating it all up, every day. Not crying, but my budget was already at zero <G>.
Water flow goes down in one day. I just checked the chlorine. Down to 1.5. Should hold algae at bay till pool shaded in 2 hours. Check pressure; hit it again, but I need fair water flow...
I'd like to stress one thing again. I have done this pool for about 40 years, and I have never had to clean the filter a 2nd time, and that was generally with differentiating levels of green. I have read that if the breather tube gets clogged up or damaged, it can cause higher pressure. I don't have one. Just a bunch of small holes in the top of the manifold. They get covered with DE, but then, they always do. They look open; no way to check.
My pool made mid-80's. No backwash, bump, etc. Pool pic - towards back is bottom of "boot", large shallow, 3 to 3.5' deep, 24' wide. I believe 16' wide in center, 18' wide top of boot, 8' deep. My memory could be faulty.
Attaching photo's...

 

[kimkats]

Down to 1.5. Should hold algae at bay till pool shaded in 2 hours.

You should do your best to NOT let the FC get that low. Every time is gets below SLAM level for you CYA, which you need to call 50, algae can grow again. It is almost like you taking 2 steps forward then 1 or more steps back.

 

[ImDudelin]

I get that... I'm between a rock n' a hard place. I have been totally unhappy with the Pentair 1.5 variable pump (medium-head) with no oomph and is big part of my problem. Where I bought it closed down years ago. I had a single speed 1 hp, hi-head, that would just keep chugglin'. It had the power to keep everything circulating, even with a dirty filter. Considering on going back to one asap. I had googled/heard that can't use a 3 hp (variable) with my inch an half pipe... I will keep trying....

 

[Newdude]

I had googled/heard that can't use a 3 hp (variable) with my inch an half pipe... I will keep trying....

We have a long line of members who disagree. You dial the VS pump down to the HP the pool needs. The larger pump moves more water at the same speed, so you run it lower for big energy savings.

 

[ImDudelin]

We have a long line of members who disagree. You dial the VS pump down to the HP the pool needs. The larger pump moves more water at the same speed, so you run it lower for big energy savings.

Like I said all the literature online said No use unless have 2" pipe. I did strongly consider the 3 hp and run at slower rpm. Shud A. It was more money, but now I'm paying for it. I don't believe that Pentair's specs/curves are accurate for my system... I cleaned filter/slammed the pool again Saturday. No time for details now...

 

[kimkats]

To clear up your pool you have to SLAM it all day, every day. Every time the FC drops below SLAM level for your CYA algae is winning.

 

[reggiehammond]

Like I said all the literature online said No use unless have 2" pipe. I did strongly consider the 3 hp and run at slower rpm. Shud A. It was more money, but now I'm paying for it. I don't believe that Pentair's specs/curves are accurate for my system... I cleaned filter/slammed the pool again Saturday. No time for details now...

I've got a 3hp Intelliflo on 1.5" piping - on a clean filter can push 80-90gpm.
When I had algae after my SWCG went offline while on vacation, flow went to virtually 0 GPM when the filter was plugged.

Would be really great if you can follow the SLAM Process and eliminate the need to worry about the filter.

 

[ImDudelin]

Thanks for replies. No details, but I've had a lot on my plate for 3 years and ongoing; should have figured this out years ago.
1st I will mention that I was unaware that you could get that much flow out of 1.5 piping. The place that I bought my pump from had other business besides pools; probably not knowledgeable enough to direct me on a better pump choice.
As to slamming all day, every day. As AJW said, I need the water circulating for the chlorine to work. Let me say what I kind of new before, and know better now. I cleaned the filter on Wednesday . Shocked early evening. Ran pump all night..Pool pressure was up 10 lbs; gpm down the very next morning. I finally stuck my hand by pump water outlet (nearest pump) and felt almost nothing. My diverter on the sweep was on all the way; Turned it off. Still very little water coming out = Waste of time running pump, but killing my electric bill. Impossible to keep slamming a pool when water is barely, if at all, circulating. Keep in mind that I cannot do a backwash. Cleaning the DE filter etc. takes several hours. Pool is down almost all day. Next---
Cleaned filter again Saturday ; pictures below. Note that I keep filling a gallon container or more of DE on the bottom of tank when I take out the grids. Is that normal? I've been reducing the DE from 8 to 7 lbs on the last several cleanings. On Wed. I tried 6 lbs. When I pulled the filter out, still had DE on bottom, but only 1/2 gallon, mostly mushy, but I also see a lot of the grids don't seem to have much. Will go back to 7 or more next time.
OK, I put everything back together. I've always put DE powder slowly into skimmer. For the 1st time I made a slush w/water 7.5lb, thinking it might be a bit different. Have to run at 2600 rpm. My pressure readings were as always: 9+ lb on tank, maybe 10. Checked water outlet. I can feel 20 or 30 times more water coming out. Good. Turned on sweep a hour later, little over halfway. Still fairly good water flow. I decided to run pump all nite without the sweep. Again, first time I've done it this way. Next morning tank pressure at 15 lb. Felt water flow some, but not really much. Up to 17.5 a bit later. Seems kind of low, especially for nearest to pump outlet. Almost forgot:
FC - 2.0; CC - 3.0; TA - 80to90; CYA this time 40. Was 45 or 48. When is the black dot really gone
3.5 gal @12.5% slam~ Results? Same as has been happening. This is not going to work out. Is it a clogged up filter, or a pump that's really not sufficient for my pool and filter system??? I'm listening <G>. I'm considering getting some TSP w/phosphates online and soaking the grids overnight. I've read that may work. In acid? Maybe, but more difficult/costly to soak.
OR, buy a new pump at a reasonable price. I've just heard that single speed pumps are outlawed in CA, but maybe I can find one... (Anybody). Any suggestions on a high-head are welcomed. Not a medium-head like I have. I'm at my wits end. Few pool service places in my area and really don't know them... Pics below....

 

[kimkats]

Take the grids out and let the water move with out being filtered while you clean the filter. The only way your pool is going to clear is if the algae is dead. You could also look into getting a cheap sand filter to use until your pool is clear.

 

[ajw22]

I explained what you need to do in post #46 and you choose not to do it.

What you did the last 40 years really does not matter as it is not working for you.

Soaking DE grids in acid will ruin them. Your grids are fine as demonstrated by the filter working after you clean it.

Focus on killing the algae with chlorine and disable the filter by removing the grids.

 

[Hg433]

I've been trying to figure what is going on, and getting worse, for two years I've now concluded that the DE filter has became plugged up with algae and/or calcium; when clean, plugs up again in few hours.

Moving from the cartridge to Sand filter was best decision i did. So, heavy to clean the cartridge filter, and it repeatedly send the algae collected back from the cartridge filter, back into the pool.