I'm not lucky enough to have an automatic system to keep my pool water topped off. When we leave for a few weeks in the hottest part of the summer, my pool would drop too far to use the skimmer. Now I just put this out there dyeing that time and it does exactly what I expect it to. Water level stays perfect.
Easy to use, inexpensive, and totally worth it.

The assembly was easy without using the instructions however I strongly urge reading them before installation. I used Teflon tape on the pipe threads to the float assembly to insure no leaks at the connection. Be sure to place the rubber washer with silt trap (cupped side) facing hose (as shown in instructions) if cup side is is installed facing the unit, it will most likely leak due to improper fit. While placing the rock or gravel ballast (weight) in the base of unit, be sure to not fill the slot around the full tube. This area needs to be free of obstacles for the prongs of the cover. The whole installation took only 20 min. The pool sentry water level control is working great and I have one less worry about my pool equipment being damaged by running dry. ðŸ‘

I've had it for two weeks and on one hand it is a life saver. The best thing I ever bought. But in two weeks it did fail once and the pool nearly overflowed. I would still recommend as a back up even if you don't trust it. I am giving it more chances to set and forget.

Can't beleive any pool builder would build a pool that would require you to use a water hose to keep your pool filled on a regular basis, duh! But this little guy is a true savior that removes the headache of constantly monitoring and filling the pool not to mention possible over filling. I live in Arizona and the summers here are hot so evaperation is constant, but not a problem with this simple yet effective gadget. Works on the same principle as your toilet tank filler. I can just imagine the light that went off in some persons head that figured this system out. It's takes 5 mins to put together, I do recommend connecting a good quality dependalbe hose that can endure the elements of all day sun exposure like the "Zero-G hose" or the RV/Marine white/blue hose which I have had for years now, both great products. Since the hose stretches from the spigot to the edge of the pool, You may want to consider putting some orange paint or tape on the hose so people see it and don't trip over it. Note: YOU MUST PUT SOME PLUMBERS TAPE AROUND THE "THREATED" PARTS (2 OF THEM; ONE ON THE HOSE AND ONE ON THE UNIT) OR YOU WILL MOST LIKELY HAVE A LEAK! The plumber tape takes care of that issue perfectly. Now turn the water on and it should start to put water into the pool. With the pool water level already filled to the mid point of the skimmer openning, I used some tweezers to grab the hard to get to white stem that adjusts the shut-off point by pulling it up and turning it counter clockwise until it shut off. I did put some farely good size rocks inside the box area to weight it down. Lastly, I make sure my hose is straight so theres no tension to cause problems. that's it check it once or twice to make sure no leaks and filling correctly, then forget about it (well maybe check it from time to time)! I can't say enough how it has taken the stress and worry out of whether the pool has enough water 24/7 especially if you aren't home for a few days, because if the water level gets lower than the skimmer opening, your pump will run dry and burn it up.

I had to buy a full replacement unit because the old one was a bit too far gone (note that you can buy individual parts from the Rola Chem manufacturing site for some parts even less than 10 bucks). This was easy to install but took some trial and error to find a decent stopping point for the water level in my pool. I recommend also buying the hose thru the same company from their actual site since the hose recommended through amazon was not rated properly for the auto-filling. I had to return the recommended by amazon hose as soon as I got it as it didn't feel safe (felt super cheap) and not worth the risk of having a potential water burst while I am at work. Other than that, great buy so far and the hose purchased from the same Rola Chem official site works perfectly.