I've had very good luck, so far, with this older style Ritchie which is steel enclosed. It works well  on a steel trough. I put a hot wire up as shown to keep the cattle from stepping on the hose etc behind the tank. Putting it on about a 12" wide (from the tank) x 4" high riser keeps them from backing up and dropping manure in it. Note sure if they still make this model but it has worked well. 

I put a 90 degree street ell, small Banjo valve and piece of black hose on the tank plug outlet at the bottom rear (you can just see a bit of the drain hose in the picture). I have found this really helps when this trough needs cleaning.  Also a short piece of pipe, a 90 deg ell and a brass hose shutoff on the inlet helps reduce the stress on the hose end and allows to shutoff water at the trough when cleaning.

This has worked well for a couple years now. 

Jim at Dawn

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