Got a new house over the summer with a pool. Learning pool chemistry in peak pool season has been fun but I managed to not get an algae bloom of any kind so far so I'll call that a win.

Got a TFP-100 test kit. Previous owner used pucks like they were going out of style… Pinch a penny of course said everything was fine but their CYA reading maxes out at 100. After diluting 1:1 with tap water I got a reading of 210. Nuts! Maintaining a free chlorine level of 16-21 hasn't been fun.

So I researched how to do a pool drain after reading about CYA on here and found out my old school '03 setup didn't have a drain to waste feature. I stumbled upon what the TFP hive-mind calls a no drain water exchange. I was concerned about pop out risk though maybe this is overblown I'd rather pay a little more in water for a process that's not 100% efficient.

Some pics below. 3 fill hoses (2 shown in pic) in the shallow end, a 1/2hp submersible pump choked down with a ball valve the other side of the pool in the deep end. A couple 5-gallon bucket tests to show my fill/drain is at about 14gpm.
A work from home Friday to check the pool level every couple hours. Ran this setup for 24 hours, ChatGPT says at 13gpm I pumped out about 20,000 gallons. Pool is 22,000 gallons.

Running the pool pump for a few hours now then will check the chemistry levels.

While it's hot like now you can drain a foot or so without worry of popping out. In winter you can do more. I drained mine in winter halfway and refilled. Went from CYA at 140 to 45.

I have struggled to maintain chlorine for a while now. How the heck are you staying at 16-21? Shocking with 2 lb every other day?

Definitely keep the sidewalls from drying out too long if you can in this heat if it starts getting low, especially on an older pool. That looks like a gunite pool and that stuff can chip and break and crack super easy if it dries out for too long after being submerged for years. Taking a water hose to it every so often during the day can help if it does get low. Refill it as soon as you can to get the water pressure back onto the walls.

Also dont forget to turn your pump off of auto cycling if it drains down below your side intake there. Will burn that pool pump up very quick if it starts sucking air.

Mine is getting up there, around 80 at last check. Got a little lazy this year and used more pucks in my combo strategy. Went back to some pucks last year when it was getting too hard to maintain with liquid alone.

Figure iit what it is. I'll do an exchange/drain and fill at some point once the weather breaks. I have tried both drain and fill like you described and draining then filling separately. Both seem to work okay

Gallon of liquid chlorine every 2-3 days yes

FC at 7
CYA at 50
TA is 200
CH is 150
pH is 8.

Added some acid this morning. Running pump for a while then will retest and see where we're at!

Retested and delighted with how it went! Working TA down and then will get hardness up but otherwise amazing. CYA is holding at 50.

TA + CH = 400 to 500 ppm

If you're going to lower your TA you need to raise your CH. your TA will naturally go down over time as you control your ph regularly unless your fill water is highly alkaline. At this point I wouldn't worry about TA and bring your CH up to 200-250.

You should test your fill water for a base line so you know what you're adding to your pool. Chances are if you have municipal water is probably a TA of 150 and a CH of 100-150.

Don't listen to pool store chemical readings and recommendations. They just want to sell you chemicals.

- pool builder

Thanks! I am keeping an eye on my CSI, it's at 0.3 right now. MUD water was surprisingly alkaline and soft also

Any recommended products? Have tested 3 times and tweaked minor stuff. Need to get CH from 175 up to 250.

It's just the pool salt, right?

Get the pool math app from TFP. Once you set your specs, you enter your test results and it tells you exactly how much of what to add. Works great. Also tracks all you test results.

That's a pretty clever setup. With CYA at 210, I can see why you wanted to bite the bullet and exchange that much water. I've been getting more into the equipment side of pools lately, and Fluidra seems to come up a lot when talking pumps, filters, and automation. Would be interesting to see what setup everyone here is running, especially on older pools like yours.

Good point.

I only install Jandy equipment. I've installed a few poolside tech automation units but they're a bit technical for 99% of pool homeowners (ie people who hire a pool service)

Dill-Ag13 said:

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Any recommended products? Have tested 3 times and tweaked minor stuff. Need to get CH from 175 up to 250.

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You just want calcium prills, preferably 94%. Dilute 1 lb of calcium per 1 gallon of water. How much calcium you need to raise your CH will depend on the gallonage of your pool. I prefer the Orenda app over TFP personally. It has a calculator to help you estimate your gallonage.

On average what is the TA of your water from the hose?

Not sure I haven't tested the TA of the water but since I exchanged 90% of my pool I'm sure it's 200+/-. Didn't realize you couldn't reduce CH chemically so I will have it sit at 175 and as the pH works up and I add acid to reduce it I will monitor CSI and adjust the CH as needed.

I've used pucks for years and this is the first time I've had an issue with high CYA. I'm assuming I should use alternate chlorine methods moving forward. Your recommendations/

Options are limited - Pucks, Liquid, and Salt, with salt being kind of its own thing.

Pucks have to have stabilizer, so they will raise CYA. Judicious use will raise it slower, so you can get years. I have done both in my 6 years as a pool owner. All Pucks, all Liquid. I have kind of settled in on a combination at this point. All liquid worked pretty well up to a point, but required daily interaction and addition. Water was awesome until it wasn't when eventually I slipped and had some issues.

At the advice of my buddy who owns a pool company, I went to the combo. Have a floater with pucks set low for a base and add liquid as needed. Has been working pretty well and is much less time intensive. Our pool doesn't get a ton of use anymore, so that helps too. Kind of accepted that it isn't the worst thing in the world to do a little drain and fill occasionally, if needed. All about balance and what works for you.

PlanoAg98 said:

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I've used pucks for years and this is the first time I've had an issue with high CYA. I'm assuming I should use alternate chlorine methods moving forward. Your recommendations/

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Liquid, preferably 12.5% strength. Use minimal pucks only to keep your CYA between 30-50 ppm. Floaters will ruin your pool's finish, get a chlorine tower at your equipment and put a check valve after your heater but BEFORE the chlorine tower.

I'm glad to see there are at least a few pool builders who know about water chemistry. Ours did a fantastic job on the build, then just turned us loose. If it weren't for Troublefreepool.com I would have been lost.

Dogdoc said:

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I'm glad to see there are at least a few pool builders who know about water chemistry. Ours did a fantastic job on the build, then just turned us loose. If it weren't for Troublefreepool.com I would have been lost.

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Unfortunately, I know more about water chemistry than a vast majority of the service companies as well it seems. Or at least, push better water chemistry. I have seen too many plaster finishes ruined by bad water chemistry. I try to give the homeowner all the tools and knowledge to do it themselves.

Main reason that I went to a salt pool, is fighting with CYA. We just replaced our cell and it lasted about 6 years, so pretty much the norm. Now we're always fighting rising pH, but that's alot cheaper to treat than a water exchange. I thought all pools had to have a waste drain to street?? Ours was built in 2000 and it's actually tied into the main sewer out, with a gooseneck outlet where I can see the water flow, which helps when vacuuming to waste to verify suction.

Usually, it's only if you have a DE or sand filter, and that's only in the last 10-15 years in my area. Most municipalities don't require it for cartridge filters, although some require it for all pools regardless of filter type.

You used to be able to install a separation tank and backwash through that tank and back to the pool, street, yard, etc.

What do you do in the winter? salt cell doesn't make chlorine under 60 degrees water temperature.

Corps_Ag12 said:

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PlanoAg98 said:

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I've used pucks for years and this is the first time I've had an issue with high CYA. I'm assuming I should use alternate chlorine methods moving forward. Your recommendations/

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Liquid, preferably 12.5% strength. Use minimal pucks only to keep your CYA between 30-50 ppm. Floaters will ruin your pool's finish, get a chlorine tower at your equipment and put a check valve after your heater but BEFORE the chlorine tower.

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Honest, question of ignorance. What difference does it make if the puck dissolves in the canister on the plumbing at the equipment or if it dissolves in a floater in the pool. Chemicals mix in the water either way, don't they?

I would *highly* recommend putting the initial dose of this in at the beginning of the summer. You don't need the maintenance doses (at least I don't). It's unreal what a difference it makes. It cheleated copper, so nothing that's really toxic.

https://www.doheny.com/doheny-super-algaecide-plus-40-oz?acctid=21700000001664618&dskeywordid=462176916394&lid=92700077918935229&ds_s_kwgid=58700008540575454&ds_s_inventory_feed_id=97700000007570802&dsproductgroupid=462176916394&product_id=1106&merchid=45111&prodctry=US&prodlang=en&channel=online&storeid={product_store_id}&device=c&network=g&matchtype=&locationid={loc_phyiscal_ms}&creative=673702640374&targetid=pla-462176916394&campaignid=20538662847&adgroupid=155021979802&gclsrc=aw.ds&gad_source=1&gad_campaignid=20538662847&gbraid=0AAAAAD_cJdrw0iS3-LkH6DfGNX7HPCcJJ&gclid=CjwKCAjw_KjVBhAHEiwAnC0N9HdGaqBlviEtu7qXoer19HYqm1gPUTM04y4QV8wQXmk1VPwhm6Dd5BoCWooQAvD_BwE

And, just to add, my CYA drops radically over the winter. They say the only way to get rid of it is drain part of the water out, but that's not my experience. My CYA is probably running 80-90 right now and no algae issues. If I wouldn't have used the above product back in May, I'd be brushing and adding liquid chlorine every weekend.

Corps_Ag12 said:

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Usually, it's only if you have a DE or sand filter, and that's only in the last 10-15 years in my area. Most municipalities don't require it for cartridge filters, although some require it for all pools regardless of filter type.

You used to be able to install a separation tank and backwash through that tank and back to the pool, street, yard, etc.

What do you do in the winter? salt cell doesn't make chlorine under 60 degrees water temperature.

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Ah ok. I still have my inline chlorinator, as I used a few pucks when we had the cell out a few weeks back. Always have some shock on-hand as well, just in case it quits working during the hot months. I seem to recall our cell was generating below 60 in the past, but I'll verify this year and see when it actually stops.

Absolute said:

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Corps_Ag12 said:

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PlanoAg98 said:

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I've used pucks for years and this is the first time I've had an issue with high CYA. I'm assuming I should use alternate chlorine methods moving forward. Your recommendations/

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Liquid, preferably 12.5% strength. Use minimal pucks only to keep your CYA between 30-50 ppm. Floaters will ruin your pool's finish, get a chlorine tower at your equipment and put a check valve after your heater but BEFORE the chlorine tower.

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Honest, question of ignorance. What difference does it make if the puck dissolves in the canister on the plumbing at the equipment or if it dissolves in a floater in the pool. Chemicals mix in the water either way, don't they?

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The floater typically ends up over a step or bench and is releasing chemicals down onto that feature. Pucks have a pH of 2.3 so they're highly corrosive. This means as it sits there dumping chemicals on your bench or step, it's eating away at the plaster.

If your CYA wasn't so high, your chlorine would be more effective and you wouldn't need the algaecide.

I thought it would something like that. Have seen the same thing on pools where the homeowner pours in their acid and liquid chlorine in the same spot over a step every time for years.

I was taught not to do that. Luckily, my floater does not get stuck like that due to the way the old pool is set up.

Yup, basically the same thing

Just one more perspective from somebody with 4 years of pool maintenance experience (so not super experienced).

Our pool (18K gallons) was built with a salt water generator b/c we didn't want to do pucks. Pool builder still added a chlorine feeder in the equipment just for backup b/c it was like $120 more. We used only salt for the first 1.5 years but I would have to add CYA increaser every 2 months or so because it would get down to 30 or less. Also had to add acid every 1-2 days, possibly from the SWG and maybe due to the new plaster.

To fix the acid dependency, I bought a 15 gallon Stenner pump and tank kit and replaced my chlorine feeder with a similar-sized PVC pipe with the pump tube inserted. I added 50/50 mix of water and acid to the Stenner tank, along with a TP Link outdoor timer, and that adds acid each day automatically and a full tank lasts about 3-4 months before I have to add more.

Adding a chlorine floater in my spa allowed me to add chlorine pucks once a week and lower my salt water generator, hopefully helping it last longer. Using both salt and pucks has meant I haven't had to add CYA increaser in nearly 3 years. I'm in the Houston area, and I turn my SWG off completely December 1st and back on maybe in March, relying solely on pucks (usually just 1-2 per week) and my CYA doesn't increase over that time.

Again, only had this pool for 4 years but it has worked well for me and I've only had CYA increase above 70 maybe twice and I can just reduce my puck usage for a couple of weeks and use the SWG more to decrease it again. I know every pool is a little different so your results may vary.

Nice I plan to dial mine in. Add pucks to maintain CYA and bolster my chlorine levels. Granted I'm not even 2 months into pool ownership, the chemistry seems easy and the key is consistency in monitoring/testing.

Like I said before, find an app you like. Makes knowing how much of a chemical to add very easy.

After a full year or so you will get a feel for how it behaves and maintaining it gets much easier.

I use pucks to start the pool season until my cya gets to where I want it. Switch to liquid chlorine vast majority of the swim season, except for vacations where I load it back up with pucks. Seems to work well. Also encourage poolrx on Amazon for a slow release of copper throughout the season…

Big fan of poolmath so far.

How much liquid chlorine do you need to put in and how often?

I've started using liquid chlorine as to not increase my CYA level any further than it is. It's expensive though. I get a four pack of 1 gallon bottles off Amazon for $50.