Trichlor Pucks In Skimmer, Bad Idea?

[Seahunt]

A couple posters who I respect said it is a bad idea to put trichlor pucks in the skimmer (in-ground plaster pool). I did not want to hi-jack another thread so I started this. They said the acid builds up while the pump is off then "jolts" the system at start-up. I am paraphrasing but you get the idea. My question is, I have been doing this for 8 years and have not had a problem. My skimmer baskets are fine and all my equipment is original (Pentaire pump and cartridge filter). I don't have a heater. I did use liquid chlorine last year and part of the year before to reduce the CYA. I really do not like the floaters in the pool. Have I been lucky or is my system (e.g., no heater) really not susceptible to Trichlor pucks in the skimmer? Thanks again!

[PaulR]

The fact is that trichlor is acidic. So, let it sit in the skimmer with the pump off, and the water in the skimmer will necessarily become gradually more acidic. When the pump comes on, that dose of acidic water will go through the pump and filter.

The risk is that this low-pH water could damage something in the plumbing; I've also heard the skimmer basket itself can become brittle. Risk is not a guarantee; it's a probability. The risk is still there even if you have not observed any consequences. (You can drive 90mph and it increases the risk of having an accident. Not actually having an accident is different from having no risk.)

I have heard of something called a Smart Stick, which is trichlor but somehow it dissolves only when water is flowing over it, not if it's just sitting. So it doesn't introduce this risk.

--paulr

[txpoolguy]

Another danger is to the interior pool surface, just outside the skimmer. The corrosive water will damage the liner, fiberglass, or plaster on the wall of the pool under the skimmer. I've seen severe damage to plaster due to this. Having said that, if you keep the system running most/all of the time, it's not as dangerous, but it's not recommended.

[chem geek]

There are some Trichlor pucks designed to work in the skimmer by not dissolving when there is no water flow -- BioGuard Smart Sticks -- but regular Trichlor pucks should not be used in the skimmer unless the pump is running 24/7 as was noted above.

7 years ago, I had Trichlor pucks in a floating feeder and they parked themselves near some stainless steel bars in my pool and rusted the mounts closest to the feeder. The acidity is very real and very destructive.

[rbdeli]

I am one who used to have a pool guy who put trichlor pucks in my skimmer. A year later I had a $700 heat exchanger repair bill. This doesn't begin to cover the costs and hassles I paid to keep metals from staining my pool the last two years. The pool guy used to leave my pump running 24/7, but I wouldn't put trichlor pucks in my skimmer at all anymore.

There are some Trichlor pucks designed to work in the skimmer by not dissolving when there is no water flow -- BioGuard Smart Sticks -- but regular Trichlor pucks should not be used in the skimmer unless the pump is running 24/7 as was noted above.

7 years ago, I had Trichlor pucks in a floating feeder and they parked themselves near some stainless steel bars in my pool and rusted the mounts closest to the feeder. The acidity is very real and very destructive.

[AFiremanFirst]

Buy a chlorine tower! and a non corrosive check valve and get your pucks out of your skimmer! Yeah you don't have a heater. You still have metal in places you haven't though of, ie pump, though most of it is stainless, or your filter, rods, rings etc. You wouldn't dump Muriatic acid in your skimmer, why trichlor.

[Groo]

Our pool has done several different types chemical releases.

Started with bromine in a foating thing. It didn't do it good enough.

then when with the bromine in the tower, very incisistant.'

then liquid chlorine, now chlorine tablets in the skimmer.

I never noticed any differences in corosion. the PVC of the skimmer and tower look very similar to me.

the basket and the metal handle of the basket seam fine.

I am not noticing accelerated aging of the liner near the skimmer.

we generally run our pool 4 hrs a day.

[chem geek]

7 years ago when I first got my pool I used Trichlor tablets in a floating dispenser. It sometimes parked itself near some stainless steel bars that are a little below the waterline. The acidity of the Trichlor rusted the mounts closest to the dispenser. So don't believe for a second that Trichlor won't cause problems. It is true that I did not notice significant deterioration of the plaster surface, but if the acidity is enough to cause more rapid rust formation in stainless steel (albeit the mounts were no doubt of lower quality stainless than the bars themselves that did not show rust), then it's enough to slowly dissolve plaster and to make vinyl thinner (you may not notice it because it doesn't get bleached -- it just gets thinner).

Some people report problems with pump seals when using Trichlor in the skimmer. So, at best, you are taking a chance unless you use Trichlor pucks specifically designed to not dissolve when there is no water flow though even then there is the report of damage even when the pump is run 24/7 (which doesn't make sense to me, but I'm just relaying what has been reported).

[quantumchromodynamics]

There are really no trichlor tabs that stop dissolving when the pump is off. Once the tabs get wet, they will continue to dissolve. I recommend that trichlor not be used in skimmers.

[salpst]

I would dump pucks all together and stick with chlorine! If want to try something, The HASAPool "Liquidator" is a better solution!

[chem geek]

BioGuard Smart Sticks claim to slow their erosion rate significantly when the pump turns off. Of course, the rate of dissolving slows down when there is less water flow for all tablets, but the implication is that these have something special like extra binders that require water flow for dissolving, not just getting wet. It might be that they just dissolve more slowly regardless of flow rate so still dissolve when the pump is off, just not as quickly, so that would still be a problem depending on how much they dissolved when the pump was off.

[Seahunt]

Thank you all. I now have a Hayward chlorine tower up and running.

[waterbear]

BioGuard Smart Sticks claim to slow their erosion rate significantly when the pump turns off. Of course, the rate of dissolving slows down when there is less water flow for all tablets, but the implication is that these have something special like extra binders that require water flow for dissolving, not just getting wet. It might be that they just dissolve more slowly regardless of flow rate so still dissolve when the pump is off, just not as quickly, so that would still be a problem depending on how much they dissolved when the pump was off.

Bioguard (and all the other Chemtura companies for that matter) also claim that CYA readings of 200 ppm are not a problem! "Nuff said?

Trichlor in a skimmer is just not a good idea. Period.

[icreatepools4u]

Chlorine pucks are commonly placed in the skimmer. This can and does cause problems in the long term. The pucks or tablets are typically composed of trichlor, which has a pH of around 2.9 . This is very acidic, and can cause corrosion of the metal parts and results in the leaching of the plastics, which eventually become brittle and weakened. The effects on the skimmer basket are pronounced when the pump cycle is low and the water does not flow constantly over the pucks.