The media could not be loaded. I bought this to use to turn our 8ft diameter stock tank pool into a hillbilly hot tub. The reviews here are hit or miss, but I have nothing but positive things to say about it. We're hitting 110 degrees, but here are a few critical tips if you're using it with a stock tank pool.

1. Wire it up to a heavy duty plug and use it on an otherwise unused gfci protected outlet. I wired mine to a heavy duty outdoor extension cord and it works fine.

2. You need to have good flow from your pump in order for it to activate. Like someone else here posted, I epoxied a large fender washer to the metal flapper arm on the outlet side of the heater. Before that, even with our 1500gph Intex pump, the flow switch would only occasionally engage (you can see this if you remove the top cover and watch when you run water through it. With the washer it engages with authority.

3. It took me about an hour at Lowe's to get the fittings together that would allow me to hook this up to my pump and outlet valve, but the most critical part was buying a length of flexible hose meant for pool cleaning accessories (also from Lowes) and a couple flexible rubber reducers.

4. The most important part that I learned was that these things take a good bit to get up to temp. I thought mine wasn't working because I felt no heat from the unit in the first hour or two. The issue was that with a large 700 gallon tank like ours, the initial heat takes a good 12 hours. The water hit 95 degrees in 12 hours, but went all the way to its max of 110 degrees within another 6. Using it with a DIY insulated cover (1.5" rigid foam and redwood fenceboards) I only need to run it for a few hours a day to keep it around 100 degrees.
Obviously this is no substitute for a 220v powered, and heavily insulated modern hot tub, but if you like the aesthetics of a rustic stock tank pool but want to use it when it gets cold, this is a solid way to go.

I understand it's not meant for this but I needed something to help boost water temperature for my pool. I installed this using a .23 pool pump and using a solar cover as well. My pool has been a nice 86 degrees even after a night of Temps in the 60s. This heater helps with heat loss at night and boosts water temperatures during the day. It also keeps the pool warm during cloudy and rainy days too.
I advise that you make sure you have the proper wiring to prevent wires melting because it does take quite a bit of power. Also always make sure you have this on a GFCI circuit with at least a 20 Amp breaker. Most importantly USE A GFCI CIRCUIT or you run the risk of getting a good zap should something go wrong.
Installation was simple. Just connect the pipes!
I wish it had an indicator light saying it was on and working, that's the reason for 4 stars.

I bought this for my 8' stock tank pool to make it a hot tub during the winter. I read other mixed reviews that had also bought it for converting a stock tank pool to a hot tub. I gave it a try because I didn't want to setup a propane instant hot water tank setup. It did take a couple trips to the local hardware store to get all the proper fittings but I got it all connected and up and running. I did run into the same problem at first of the heater not kicking on so I tried taking the top cover off like others said they did and I tricked the switch to be on. Also I did have to plug it into a 20 amp plug. While I was trying different things, I had changed the filter on the Intex 1500 filter pump and noticed the flow switch was working like it should so I put it back together with no modifications and it works great, I just change the filter every 2 to 3 weeks and have no issues. I did also buy a Bayite temperature controller plug and plugged the filter pump into it on the heat plug and have the temp set to turn off at 100° and have it kick back on at 98°. I did have to change the plug on the Intex filter pump to a non GFI plug because every time the temperature control plug shut off when it reached 100° the GFI plug on the pump would pop off. I have had no issues in 2 months now and am loving it. It did take a few days to get up to temp, I live in the foothills of California and the temp here recently has been in the high 50's to low 60's during the day and mid to high 30's overnight and it keeps it to temp with no problems. I have a blue bubble cover and a black 8' pool cover on it to help keep in the heat.

This thing is great but it's not made for small pools so you'll need to be crafty. I have mine connected to a 10x30 pool and is heated to 84-88 degrees.

First it's meant to be hardwired for 20amps but I put a 15amp plug on it which is plugged in to a 15amp GFCI outlet and have not had any power issues. Make sure to put the white wire on the proper side. Examine your outlet if you need to.

Next, the PVC couplings, be prepared to spend time finding the parts to connect your pool hoses but it can be done relatively cheap at your hardware store. Also, metal o-ring clamps will help a lot to eliminate any leaks.

I upgraded to a stronger pump filter, it's still not quite enough to trigger the flow lever. Others have added a metal washer to create a bit more surface area but I decided to super glue a lego brick under it which means I have to be very careful and ensure it's only plugged in when the pump is running otherwise it will pop the heater's hot circuit (under the little screw cap) and potentially break the unit. This is how I broke my first unit.

The most important concept to consider is the relationship between heating your pool and water flow. As water is flowing through, the water is picking up a little bit of heat from the coils each time and then going back in the pool and sharing that little bit of heat with the rest of the pool.

The little pump will not move the water fast enough to warm the pool. I upgraded to the 1500 gph and to 1.5" hoses using hose adapters.

You also should start with warm water otherwise it's 2-3 days of running 24 hours to get the pool warm. After it's warm it needs about 6-8 hours a day to keep it warm and surprisingly I didn't see a huge difference in my power bill.

Last connect to output of the filter pump; after the water has been filtered. No need to get leaves and dirt stuck on the heating element.

Good luck.

I bought this heater understanding that it had limited functional uses. Specifically, it could hold temperature much more readily than it could bring a non-heated body of water up to temperature. Also understood it cannot be used with a weak pressure flow pump, or for large volumes of water. So far, my experience is that the pump will not provide any heat whatsoever. I have had it professionally installed (union plumber) and have paired it with an spa-industry standard "Grundfos" circulating pump.

Drained the tub today and "un-installed" the heater. Confirmed that it does heat when the flow switch is tripped and the dial is rotated calling for heat. Problem has to be the flow switch not tripping due to a lack of sufficient water pressure from the 3/4" pipe I used. Like other reviewers, I epoxied a larger plastic "washer" piece (I used the bottom of a pill bottle) onto the trip lever. My thanks to other reviewers for emphasizing the units integrity if installed per the mfgr. Specs. Will post further after installation and testing.

UPDATE: More frustration as the large "washer" I installed apparently reduced waterflow too much; resulting in pump surging. I fabricated a metal (not plastic) trip lever extension that closely matched the existing trip switch and I attached it mechanically rather than with epoxy. RESULT: This Heater will HEAT! I left the system on overnight and discovered the temperature to be at 112° the next morning. Now that all the components seem to be playing nicely together, all that remains is to calibrate the temperature dial to real world experience.

This product would be improved greatly by the simple addition of a small indicator light that shows "on" confirming when the heater is actually heating.