Can't get rid of very fine dirt in pool

I imagine that not being able to get ALL the dirt out of a pool is probably a pretty common problem, so I'm hopeful that those here that have "been there done that" can offer some suggestions.

I have a very small pool which I built for my dog. It's 17' x 8' and only 2 feet deep - approx 2,000 gallons. Can be seen on this thread if you need more information that that.
concrete-block-puppy-pool-in-progress-many-questions-t67964.html

The pool has a small Hayward sand filter / pump combo unit. 40 some pounds of sand in filter.

I did several searches on this and the most common answer seems to be to backflush while vacuuming to carry the dirt out of the system. I've tried this multiple times and the fine dirt ALWAYS comes back by the next day, so it's not being backflushed out.
I vacuumed (on backflush) about 4 inches of water out of yesterday and the dirt is back on the bottom today like nothing happened. I suppose it doesn't hurt anything, but I sure would like to have it gone!

I'm talking VERY FINE dirt here, like swish around what collects on the bottom and you can't see it anymore. But, it seems to collect together and LOOKS like much bigger dirt when it's settled.

Being that a dog is the main pool user, I do have a sock type extra filter that I use in the skimmer basket to keep the dog hair from getting into the filter. It just doesn't catch the fine dirt. I've researched adding DE to the filter sand, but (from what I've read) it doesn't seem like even that would trap the fine dirt.

I'm to the point where I am considering using a shop vac (remember it's only 2 feet deep, so that's doable) but, I'd probably have to do this quite often and I'm looking for a better solution. The shop vac idea would be a lot of work!

I'd very much like to hear of any other cleaning suggestions to remove this very fine dirt, because I have a LOT of it and can't seem to win this battle.

Thank you.
 
Probably at least 3/4 of the time, fine dirt that keeps coming back is actually algae that is just barely being supressed. How do you chlorinate, and what are your readings?
 
Doesn't algae grow on something? Meaning like it's more stationary unless disturbed by brushing or something like that? This stuff I have isn't on the walls or where walls meet the floor, and I'm pretty sure it's simply dirt that the dog tracks in from lying the dirt yard. Could be wrong...

I add chemicals using a measuring cup and putting in whatever my wife tells me to! :p Her part of this pool project is to keep up with all the chemical readings and I'm happy to have her involved. Bought her the best test kit that they had for sale at Leslie's, so all the tests are covered.

Chlorine is tested daily (at 3ppm today) - usually add 1 cup 10.5 clorine every other day or so. (less than 2,000 gal pool)
PH tested every other day (7.5 last I heard) I haven't had to add muriatic acid in about 2 weeks.
CYA was 80 last week - I may have to add some stabilizer as I've added a bunch of new water lately, will have her check it soon.

Don't know the other stuff, but she checks it! Know she checked calcium last week and even that was good. She checks everything all the time, so I'm not thinking we could have algae. Could be wrong as I'm new to this pool stuff.

I've never shocked the pool (it's only 3 months old) as I didn't think that needed doing unless the chemical readings were off. Does that matter?

I really believe it's just dirt and I just need to figure out a way to get it out.
 
Vac to waste not backwash. Backwash still goes through the filter, an some may be getting caught an when you put it on filter it comes back in. Waste bypasses the filter straight out of the pool
 
The valve control on top of the pump has 4 options - Filter, Closed, Backwash and Rinse. Nothing that says Waste.

Is Rinse the same as waste? I thought Rinse was what I did after a backwash to "pack the sand back down" in the filter. That's what I've been doing anyway, rinse after backwash.
 
I rinse after vacuuming to backwash. Not when I just do a normal vacuum.

Just read the filter manual again and it says:

RINSE - After backwashing, with pump off, set valve to RINSE. Start pump and operate for about ½ to 1 minute. This ensures that all dirty water from backwashing is rinsed out of the filter to waste, preventing possible return to pool. Stop pump, set valve to FILTER, and start pump for normal filtering.

Sounds like I need to try the vacuum with the valve on rinse instead of backwash?
 
Overnight with filter running.

This is a picture of the filter/pump setup from before I filled the pool.

Pool-H.jpg


I'm not sure how you mean I could add a separate Waste line? Seems everything from the intakes has to go through the pump (and filter) before I could do anything else.
 

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Probably at least 3/4 of the time, fine dirt that keeps coming back is actually algae that is just barely being supressed. How do you chlorinate, and what are your readings?
+1 what JohnT said.

Before you start modifying your plumbing, your water needs to be free of algae and not all algae grows on "something".

Post some test results and tell us how often you chlorinate and with what and how much. Also tell us which Leslie's kit you purchased.
 
Always in the same areas everytime. I have 4 returns and the dirt settles where their outflow doesn't disturb the dirt.

If I adjust the return jets (I have) the dirt just settles where the repositioned jets allow as they can't swirl all the water everywhere.

Thank you for your replies, I appreciate the time you are taking to help.

Still hoping for some magic cleaning trick easier than the shop vac route!
 
I got the Leslie's "Total Poolcare DPD Test Kit". I've read that they have a better one, but this was the best they had in stock at that store.

What test results should I post other than the Clorine, pH, CYA stuff above? I don't do the testing, but I can post other results in about an hour. I know alkalinity is also at the proper level (whatever that level is!).

No, I have a regular vac that I hook up with a hose that runs through the skimmer basket.

My problem is the "dirt" is SO fine it just passes through the filter, so I was thinking that with a shop vac I could just vacuum the "dirt" right out of the pool into the shop vac. It's just going to be more work that I care to do as the dog will just bring new dirt back in the water next time she gets in.
 
okay... I was looking at the pump/filter and I'm thinking that if I disconnect the hose between the pump and the filter up top at the filter end that would give me a "Waste" output. I can hook another hose to that short hose to give me a way to pump water away from the pool area while using the vacuum.

This should allow me to vac up the "dirt" and not have it go through the filter and back into the pool.

A trip to Home Depot for a hose to hose connection piece and this might just work.

Thanks for all the help and the "Waste" (filter bypass) idea!
 
bob2112 said:
Doesn't algae grow on something? Meaning like it's more stationary unless disturbed by brushing or something like that? This stuff I have isn't on the walls or where walls meet the floor, and I'm pretty sure it's simply dirt that the dog tracks in from lying the dirt yard. Could be wrong...

Chlorine is tested daily (at 3ppm today) - usually add 1 cup 10.5 clorine every other day or so. (less than 2,000 gal pool)
PH tested every other day (7.5 last I heard) I haven't had to add muriatic acid in about 2 weeks.
CYA was 80 last week - I may have to add some stabilizer as I've added a bunch of new water lately, will have her check it soon.
...

Sounds like dead algae. Your chlorine level should never, ever be allowed to drop below 6 with a CYA of 80. See: pool-school/chlorine_cya_chart_shock

I think you have algae in your water like JohnT said. Algae is present before it becomes visible. The chlorine is killing it, and the "dirt" you see is actually dead algae. Dead algae often looks like very fine dirt particles that cloud up when disturbed, then resettle. Vacuuming it to waste is removing it, but then more algae is killed because the chlorine level isn't high enough to prevent algae, and so it looks like the "dirt" never goes away.

Try SLAMming, and see if that gets rid of the "dirt": pool-school/shocking_your_pool
 
The more you post, the more it sounds exactly like algae barely being controlled. At 80ppm CYA, your chlorine should be kept around 9ppm and never allowed to drop below 6ppm.

Dead algae collects on the bottom and is so fine you can't feel it and a vacuum just stirs it around.
 
What they have all said, it sounds like your Chlorine (FC) level is too low for your CYA, in order to measure FC over 5 ppm you will need a FAS-DPD chlorine test to add to your Leslies relabelled version of the Taylor K-2005 that you currently have, the good news is you don't need to buy a whole new test kit, just the FAS-DPD single item test to add to your current kit, you can buy this at tf test kits, see the link in my signature.

Ike

ps better yet click here http://tftestkits.net/FAS-DPD-Chlorine- ... t-p47.html
 
Looks like a consensus of opinion among the "been there done that" folks - and I am listening!!

Being a newbie, I had kinda thought that if I got algae that I would either see it on the walls or floor or that the water would get cloudy. Guess not... seems I still have plenty of learning to do.

I had wondered how to test for chlorine levels over 5ppm as that's as high as my test kit goes and then Ike even answered that one for me - thank you sir. And thank you all for the schoolin'!

Got some work ahead of me, but doesn't look like anything I can't handle - now that I understand what I'm dealing with.

I do have a question. I've been keeping the pool very warm, talking 85° to as high as 95° (not heating it this week due to a cold front coming through) so are there any special considerations, like different chemical balances, that I should be aware of when dealing with warmer pool water?
Oh, 2nd question - Will the water being cool (probably going to get down to the low 70s or cooler with this front coming through) change the treatment to kill this algae off?

Thanks again guys. Hopefully I'll have this problem licked by next week when it's time to heat the pool back up for puppy swimming!
 
Warmer water will help the algae grow more quickly, but also growth does not really slow down until the water gets down into the 50's. Overall treat 70-90 degree water the same, you will just likely see a bit faster chlorine consumption with the higher temperatures (it will take more chlorine to maintain a given FC level with warmer water).
 

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