Pond pumps: mans or low-voltage?

[Bert Coules]

Any opinions on the relative merits of mains-powered pond pumps as opposed to low-voltage DC? One advantage of the latter might be that it's safer to run non-mains cabling into the garden (though presumably it still has to be buried and protected); one disadvantage could be possible voltage drop, I suppose. I'd be looking at a run of around fifty feet.

Thanks.

[Bert Coules]

To partially answer my own question, I've just found this on the TLC website:

"Low Voltage pumps use a 24v supply from a mains transformer and as low voltage connections require no tools, installation is a straightforward inexpensive task. No extra cable protection is needed. The cable can be extended up to 50m. Our low voltage pumps have identical performance to their mains cousins."

"No extra cable protection" is a little surprising.

[Chris Green]

I have recently moved from mains submersible pumps to 12 volt ones and I wouldn't go back now. The 12 volt ones seem smaller (quite a lot smaller) for the same amount of oomph, they're just as quiet and they seem to be cheaper as well.

To run the 12 volt pumps I originally had a 12 volt (ex vehicle) battery and a charger but I've now bought a couple of 12 volt switch mode power supplies (intended mostly for LEDs I think) instead, also very cheap.

This is the smaller of the two 12v pumps I bought:-

... and this is the power supply I'm using (for both pumps) :-

As you say, apart from anything else, I feel much safer groping around in the nether regions of the pond now. Though it does of course still rely on the isolation in the PSU.

[Bert Coules]

Thanks, Chris. I'm surprised at the low cost of the pump. Did you bury the cable at all?

[Andy Burns]

At those prices, I'd be worried it was too cheap to last long.

[Chris Green]

No, the mains feed to a little shelter (built of bricks) beside the pond is buried SWA but I've left the 12 volt stuff from there to the pond unburied.

[Chris Green]

I've not found any correlation between price and lifetime! :-)

My first relatively expensive mains (branded, like Hozelock and such) pumps didn't last any longer than the rock-bottom priced ones (still mains) that I bought from AliExpress etc.

I've not had the 12 volt ones long enough to make any comments on their life yet.

[Bert Coules]

Thanks, Chris.

[Brian Gaff]

One assumes then that the power supply is universally protected against shorts. Brian