Problem with curing tank

[mvanaken]

My concrete lab has five curing tanks. Two of these tanks have started to develop a thin layer of film on the surface of the water. Each tank has a heater to maintain constant temperature, pumps connecting tanks to ensure water circulation and are all oversaturated so the excess lime has fallen out of solution and collects on the bottom.

Sometimes the tanks become so loaded with cylinders that they create "walls" within the tank that act as barriers impeding the flow of water from the pumps. I'm not convinced that the film is a "lime scum" caused by the stagnation of the water because of this, but I do think it could be a possibility. Does anyone have any insight as to what the cause may be?

Below is a referenced thread from a few years ago where the OP had the same issue and no one seemed to answer the question. Thanks!

thread592-264388

 

[dicksewerrat]

Pull a sample and have it tested.

Richard A. Cornelius, P.E.

http://WWW.amlinereast.com

 

[BigH]

Could the "slime" be a result of dust other air-laden detritus in the atmosphere falling onto the water - we get it here in the outside tanks in Asia - and we skim it off . . . mosquito breeding grounds!