[WC] de-mineralised water
 

Is it ok to use de-mineralised water, or is it still better to use distilled water?

i tought those where the same!

distilled < de-mineralised < de-ionised water

so de-mineralised is even better?


Excellent!

no that's wrong.
the list should be:
de-mineralised < distilled < de Ionized
(If De-Ionized is what I think it is.)
de-mineralized just means that the calcium of the water has been replaced by sodium (Na).
Distilled is boiled and condensed water. This should be 100% pure water.
De-ionized water is water that hase it's native ions (OH- and H+) reduced so that it conductes even less electricity (as said before, I think.)

I think demineralized is better, because it doesn't contain chalc (lime)

google stuff:

While distilled water still contains some mineral content, it will likely contain lower mineral content than most tap water. Distillation is the most effective method for removing minerals from water.

Two additional demineralization processes, deionization and reverse osmosis, remove most of the minerals from water, but are generally less effective than distillation. Water demineralized by these two processes would, on the average, be expected to contain a higher mineral content than distilled waters. "Purified" water may be produced by any of these three or other similar processes.

Distilled water gains ions over time adding to it's conductivity(if thats a word). Not just from mixing with air either, it will gain the ions just from touching the metal water block in a water cooling system

TeuS, good explanation.

By the time you add anti foaming and Glycol for lubrication to the pump plus the reaction with copper or alum, you would have to flush the system once a year if not more.