Mark SJ

Thanks, I appreciate you taking the time to respond. I will check out the links you posted. The reason for posting here is I believe the members here have more experience on the bacterial side of things as it will be devoid of life and used for swimming activities.

Looking for helpful advice an opinions, so far I have had so much conflicting information thrown at me! 18 months ago I drained and enlarged a lake. It is now 150m x 100m with an average depth of 4m, with some parts as deep as 10m. The soil all around is a sandy clay, and at the moment at the bottom at the moment there is around 20cm of silt. There is virtually no vegetation around the outside of the lake, no animals and there are no fish in the lake whatsoever. The lake itself is filled by an underground aquifer and run off from rain water. The temperature here in Thailand is general