I am renovating an old backyard farm pond used for fish production for family consumption as opposed to commercial fish farm. I have seen several backyard ponds with stone and concrete linings. That would seem to be a big help with preventing erosion of the banks of the pond. I am thinking of using concrete and stone on the sides of a 15x20m pond leaving the bottom mud. What issues are there with the lime in the concrete altering Ph levels and how does one manage that?

Many thanks.

Hi. Regarding you enquiry about using cement in your pond modification, you have no reason to worry about toxic output or change in p.h. levels. There are however some things you need to consider. Make sure the cement is completely dry before filling with water. With the size of your pond I would imagine it will take at least a week to dry out. Once the cement is dry it will not give off toxins. When it is dry fill the pond with water and leave it for 24 hours and then drain the water out, refill and leave the water for another 24 hours before adding fish.

here is a pic sowing a tank I made using cement. There are now 100 Tilapia fish and 40 redclaw crayfish in it.

If you use the cement blocks ( used for house construction) be sure not to expose them to the water as they are toxic, they contain flyash which will kill your fish. They ned to be completely covered with a rendering of cement.

If you want more info you can look at my thread on this forum called " breeding crayfish"

Good luck

crayfish