Swimming pool antifreeze is non-toxic antifreeze and can protect swimming pool pipes down to -40°, when added in correct proportion.
Here’s some Q&A regarding the use of pool plumbing antifreeze.
Q: Is swimming pool antifreeze necessary? A: If you blow out your plumbing lines correctly, and if there is no water in the pipes to freeze, then there’s no need to use antifreeze. However, many folks like to use antifreeze as additional insurance against faulty plugs, extremely cold winters, or if you’re not really certain that all of the water has been blown out.
Q: How much pool antifreeze is needed? A:Most manufacturers advise to use 1 gallon of pool antifreeze for every 10 feet of 1.5 inch pipe. This assumes that the pipe is full of water however. If you are adding it to an empty pipe (or near empty pipe), you can generally use ½ gallon per line.
Q: How do I add pool antifreeze? A:After lowering your pool water to the winter level, you can pour it into the skimmer before plugging to protect the skimmer line.
Q: Can I pour it into the pump, filter, heater, chlorinator? A:NO! Remove the drain plugs for your pool equipment, and better yet, some air to remove the water. Using antifreeze in your equipment can cause damage, as the salts and glycol will react with metals and rubbers. Antifreeze also reacts dangerously with chlorine, so be sure not to add it to a chlorinator. It will gum up a pool filter. I repeat, do not use antifreeze in your equipment. If your pump sits below water level and you have concerns, just leave the drain plugs out all winter, or remove the pump and store it indoors.
Q: Can I pour antifreeze directly into the pool? A: Some of you may be laughing at this question, but it’s been asked many times. NO – the pool will freeze, and you would need a LOT of antifreeze to prevent it from freezing. Pool antifreeze is not for the pool, but for the pipes. For aboveground pools, you should use an air pillow to break up the ice sheet that forms in the pool, or you can use half a dozen milk jugs, filled partially with pebbles and pool antifreeze, to absorb the ice expansion.
Q: Will antifreeze protect a main drain line? A:Maybe, but keep in mind that antifreeze is heavier than water, and it will seek the lowest level in the pipe. If your main drain pipe has a steady pitch, as many do, you may notice the antifreeze coming out of the main drain, into the pool shortly after adding it.
Q: Will pool antifreeze harm the pool if it gets in the water? A:NO, it’s specifically non-toxic and won’t have any effect on the water chemistry and is not dangerous to swimmers. However, most people I know will that use antifreeze will start up the pump with the multiport valve on waste, to pump the antifreeze out of the backwash line. If you have a cartridge filter this may not be possible, so no worries, just let it mix with the pool water.
Q: Can I use Prestone, or other automotive antifreeze? A:NO! Ethylene Glycol is very toxic, and should never be used. Make sure the bottle is labeled Pool Antifreeze, which contains propylene glycol.
Q: Will pool antifreeze harm my pets or wild animals? A: Non-toxic pool antifreeze should not harm animals, but if they drink it, it will likely cause an animal to become sick. Automotive antifreeze is definitely dangerous and can lead to kidney and liver problems, if not death.
Q: Should I pour Pool Antifreeze in the skimmers after plugging the hole? A: NO, this makes a scummy mess come spring, and it can attack rubber plugs, or the o-ring for threaded skimmer plugs. The better solution is to use a GIZZMO, a long, threaded, plastic device that screws directly into the skimmer acting as a plug but also will absorb expansion when ice forms in the skimmer.