Hydro-static Reliefs Valves With Preformed Ponds?

[mikecoscia]

Anyone ever use them on rigid preformed ponds? I am in the process of installing a 125 gallon and 30 gallon preformed pond interconnected with streams. We had some heavy rains yesterday and the hole I started to dig is literally filled to the brim with water and draining slowly. The soil is all clay, so I new it might be an issue and was planning on doing a concrete skirt around the pond and cementing the slate to that and lip of the pond. However, now I am thinking it might not be enough and was looking into hydro-static valves. Has anyone used them on a smaller pond? The larger pond is only 2' deep, do you think it will be enough to pop the valve when needed? The required pressure is 1.25 lbs. Appreciate any suggestions.