How to add large batches of CYA

[Newdude]

Hey Folks !!!

With a large pool, I need 4lbs of CYA to only raise it 15, and I don't think I have that many socks without holes in them. So I use a Tshirt. Plus, I like that it's doubled up for redundancy. But it can also be scaled down with socks.

So I measure out my dose and can get 4 lbs in my kitchen scale. If I need more I do 4+2, etc.




Then I dump it on the chest.



I sack it up careful to get all the sides and tie it off



Then I roast tie it for support and add a loop to hang it.



I weigh down the pool pole so it doesn't tip in and soak the bag in front of a return. You want it just far enough to be way clear of the wall, but close enough it still has good movement.



With warm water these days. It's mush 2 hours later. In the spring I let it go a full day. This part was hard to get a pic while shaking, but you get the idea. Some squeezes and a bunch of shakes and it comes right out. Brush well after.




5 mins of making clouds later, just a little is left. The shirt gets hosed off and sun dried for next time.

 

[Flying Tivo]

 

[Newdude]

It was a smiley face when I first opened it.

 

[Texas Splash]

 

[98valkyrie]

Great write up, thanks!

 

[WaterwayHaven]

Inspired by your approach

 

[HitchHiker]

Is there an advantage of using the powder as opposed to liquid forms of CYA? Just curious as I chose two gallons of liquid CYA yesterday and put it slowly into the skimmer - then brushed the pool twice afterwards. AT 25000 gallons I still need to put more in, as I cannot get a measurement using the TFP Pro test kit this morning. I can still see the black dot at the base of the plastic vial after filling the entire vial to the top with treated pool water, but I just realized I used the wrong instructions (TFP 100 instructions), so now I have to re-run the CYA test.

 

[Texas Splash]

Is there an advantage of using the powder as opposed to liquid forms of CYA?

Cost is the big one. Once fully dissolved, the CYA typically registers the next day.

Liquid usually regiaster very quickly - just a few hours. I'm not a fan of pouring directly into the skimmer, so perhaps that thick stuff is still sitting in the filter trying to break down.

 

[proavia]

Is there an advantage of using the powder as opposed to liquid forms of CYA?

More money left in your podket at the end of the day.
Liquid CYA is WAY more expensive than granular based on actual level of CYA added.

2 gallons of liquid stabilizer in 25000 gallons should raise CYA by 30ppm.
6.25 pounds (100 oz) of granular stabilizer in 25000 gallons should raise CYA by 30 ppm.
I'll let you do the math to compare the cost.

 

[Dirk]

I once used liquid CYA, and tried to pour it directly into the pool. But the "liquid" quickly separates in the jug without constant shaking, which I didn't realize. The final bit came out of the jug as a big slug of semi-solid CYA, which quickly sank to the bottom. In the few moments it took to run and grab my brush, the slug stained my brand-new pebble finish. So no more liquid CYA for me, and I'll never put any type of CYA directly into the pool again. Not in a sock, not in a t-shirt, not hung in front of a return, not no how.

I now use CYA granules in a very fine-mesh laundry bag, and hang that in my skimmer. The bag has a zipper, so none can escape. No knots to tie. And it's semi-transparent, so I can easily see what's left in the bag. It's easy to bend down by the skimmer lid and squeeze the bag a few times. No hanging contraptions to undo-redo. The bag is trapped in place by the skimmer lid, so that it hangs above the skimmer basket (instead of laying on the bottom of the basket), to allow for good flow. When done, the bag is easy to wash out and it dries quickly. It rolls up nice and small and gets stored in my pool "tool box."

Yes, some amount of CYA might get temporarily waylaid in my cartridge filter, but so what.

The one I have is similar to this. They come is all sizes, and different mesh "finestes." I found one with a very tight mesh that is just the right size for my skimmer. They also come in very large sizes, so could theoretically hold large amounts of granules.

Walmart Mesh Bag

As in all things pool, you find and do what works for you. If the hung t-shirt is your thing, then do your thing. This is what works for me.

 

[Newdude]

It's also real hard to dose less than a full jug of liquid CYA as it all clumps up on the bottom and you pour water, water, water, water, WAY too much.

 

[HitchHiker]

I once used liquid CYA, and tried to pour it directly into the pool. But the "liquid" quickly separates in the jug without constant shaking, which I didn't realize. The final bit came out of the jug as a big slug of semi-solid CYA, which quickly sank to the bottom. In the few moments it took to run and grab my brush, the slug stained my brand-new pebble finish. So no more liquid CYA for me, and I'll never put any type of CYA directly into the pool again. Not in a sock, not in a t-shirt, not hung in front of a return, not no how.

I now use CYA granules in a very fine-mesh laundry bag, and hang that in my skimmer. The bag has a zipper, so none can escape. No knots to tie. And it's semi-transparent, so I can easily see what's left in the bag. It's easy to bend down by the skimmer lid and squeeze the bag a few times. No hanging contraptions to undo-redo. The bag is trapped in place by the skimmer lid, so that it hangs above the skimmer basket (instead of laying on the bottom of the basket), to allow for good flow. When done, the bag is easy to wash out and it dries quickly. It rolls up nice and small and gets stored in my pool "tool box."

Yes, some amount of CYA might get temporarily waylaid in my cartridge filter, but so what.

The one I have is similar to this. They come is all sizes, and different mesh "finestes." I found one with a very tight mesh that is just the right size for my skimmer. They also come in very large sizes, so could theoretically hold large amounts of granules.
View attachment 590176
Walmart Mesh Bag

As in all things pool, you find and do what works for you. If the hung t-shirt is your thing, then do your thing. This is what works for me.

This here is exactly why I went through the skimmer. We just spent $30k on a pool reno and a higher end more costly finish - NPT Stonescapes Puerto Rico Tropics Blue small pebble blend with added Jewelscapes and abalone shells. I don't want to risk damaging the brand new plaster/pigment. I like your idea of using a mesh bag if/when I switch over to the granules. The instructions from my pool renovator are not to use any granulized chemicals for the first 30 days at least - liquids only - whether chlorine, acids, etc., all liquid - and whenever possible - through the skimmer (exception being muriatic acid).

 

[Dirk]

The instructions from my pool renovator are not to use any granulized chemicals for the first 30 days at least

I could argue that, especially for CYA, but it's more important to follow the warranty issuer's instructions to the letter.

If I was forced to pour liquid CYA into my skimmer, I'd still use my mesh bag, and pour it through that. When that inevitable big glob falls out, it'll get trapped in the mesh and then can dissolve properly from there. That would avoid sending a large slug of acid directly into my filter.

 

[HitchHiker]

It's also real hard to dose less than a full jug of liquid CYA as it all clumps up on the bottom and you pour water, water, water, water, WAY too much.

Yes agreed - you really have to shake it up for 30-60 seconds before dosing, and it's much easier to do one gallon at a time given how much it clumps up.

 

[HitchHiker]

I could argue that, especially for CYA, but it's more important to follow the warranty issuer's instructions to the letter.

If I was forced to pour liquid CYA into my skimmer, I'd still use my mesh bag, and pour it through that. When that inevitable big glob falls out, it'll get trapped in the mesh and then can dissolve properly from there. That would avoid sending a large slug of acid directly into my filter.

Agreed - however worst case I can replace my 48 sf DE filter medium for $200 a pop - I cannot replace the $17k new plaster in comparison.

 

[Dave31410]

I have a pool net that is about 12 inches deep. I put the CYA in the net in front of an inlet, with the handle lying across the deck.