HiLetgo 2pcs Water Pump 240L/H DC 12V 4.2W Micro Brushless Pump 3M Pumping Head Ultra Quiet Water Pump for Pool Aquarium Fish Tank

Very good functionality, pumps and flows well, durible, easy install. Use a filter to keep debris out of impeller.

Cool little pumps and very quiet

I’ve purchased many of these small fountain pumps. I use them water potted plants with a timer, battery, solar panel setup. But they don’t last long. Maybe 2 to 3 years outside.

I ran mineral spirits through this pump into a clogged A/C condenser. Powered the pump via a bench power supply. I ran the pump for about 10 hours stopping every couple hours to blow the condenser out with compressed scuba air. Even back blew through the pump several times.After about 10 hours of use it quit pumping. Removal of the 4 screws on the pump face revealed biological material in the impeller which was easily removed and pump easily reassembled.Pump functions as new after removing debris from impeller.

These are super tiny and they have no way to plug them in without splicing something

You get what you pay for, theae are cheap in cost and ability. But if you treat them correctly they will workBut don't let any debris get in, the pump will seize up and you need to remove the tiny 4 screws and remove the debris.However, because of the design, clogging the pump and causing it to seize will not hurt the pump.The pump.needs to in the chamber to work. One little air bubble and the impeller will spin ans not pump liquid.

Work great at a great price.

These are great for the price point.When they are working they move the expected amount of water. Pressure is proportionally weak, but that is a side effect of spending the available energy budget on flow/volume/mass. You would need to move less volume to get a higher pressure for the same watts, that's just physics. With a hose the same ID as the barb, I get about 2-4 feet of lift before back pressure causes it to stall, which is damn good for the flow rate and the sub 20 Watts honestly.The biggest con is they are bad about cavitation and priming. You have to be very particular about keeping the input loaded with only water. Even as small as a few CC's of air will cause stall/cavitation. The problem can be worked around easily if you have a level head on your shoulders.Basically, these are ideal for relatively high flow and reasonably closed loop applications. Liquid cooling PC's, fish/fountain pumps, etc. Not as great for situations where the input is getting exposed to air, or expected to start from an air locked state. Definitely not good for anything that relies on pressure to get the job done, e.g moving fluid against gravity, spray washing systems, etc.Haven't used them for anything other than fresh water, so I don't know what other liquids they could handle.