Contaminating RO water

[reef dude]

I was told that it is very easy to contaminate RO/DI water. I heard you should always wash your hands, keep the water covered, etc..... before handling the water. Is that true??
Obviously if your hands have soap or ammonia on them, that will contaminate/affect the water, but how sensitive is it to foreign substances?
for example, if a drop of tap water fell into some RO water, would that completely ruin the RO supply, or would it just be one drop of tap water in a bucket full of clean RO water????

 

[bonermeister]

It is not as drastic as you're making it out to be. One drop of tap water in a bucket of RO/DI is exactly that: a drop of tap in a bucket. No big deal. Of course you do not want to dip your hands in with cologne/perfume or anything else on them. You might have heard a twist that RO/DI water can fluctuate greatly in pH because it has no buffers, this is only the case if you use it in freshwater systems. Once you add your salt supplement to it and your Ca and/or Kalkwasser it is all set to go.

 

[broomer5]

pure water - especially deionized water acts as a mild acid.
Water does not like to remain in a deionized state. It want's to grab a hold of other ions and become what most natural waters are ...... IONIZED.
DI water does not exist naturally .... we make it by removing ions.
So ........... as it comes in contact with other substances .. it tends to "attack" these substances, and dissolve them.
DI water can be kept in glass containers, or glass lined piping systems .... and this helps to maintain it as "deionized".
Most anything else .... especially metal containers or piping, will "contribute" ions to the DI water ...... making it less deionized sort of speak.
DI water does not "like" to be deionized. So it can become "contaminated" as you stated .... by most anything it comes in contact with.
But ........... for our use in this hobby, as long as you keep it / store it in a plastic, rubbermaid or glass container ..... it no big deal.
1 drop of tapwater ( which will contain ions like sodium, calcium, magnesium, etc. ) placed into 10 gallons of DI water - will only contaminate the DI water with whatever ions were present in that 1 drop of tapwater. No more .. no less.