RO/DI TDS 116 x10

[oopsmybad]

So I was filling up my salt mixing 40 gallon breeder to do a water change and just for the heck of it I tested the RO/DI water I had filled it up with. It said 116 x 10 on my TDS. The TDS coming directly out of my RO/DI is reading 2. I have been using this mixing glass tank for a while and have mixed many batches of salt water in it. So I figured there is just some left over residue from previous salt mixings.

Not sure if this is something I should be worried about? I did check for phosphates and they are at 0 in the mixing tank water.

 

[tmz]

I don't know abut the mixing container but tds over 0 post di means the resin is exhausted.

 

[bertoni]

Once the RO/DI is stored in a container, there's likely to be a little leaching and carbon dioxide will enter the water column. Both effects will raise the pH.

I agree that 2 ppm out of the RO/DI means the DI is shot. That can be a problem:

http://reefkeeping.com/issues/2005-05/rhf/index.htm#7