What's the difference, if any ?

[colin m]

We shouldn't (although we do) use tap water anyway as the chemicals used for treatment have a bearing on the reaction to the paint ..especially in hard water areas.You can try a little test... mix paint with tap water, distilled water and some water from a river/loch/lake then paint each onto the same bit of plastic... you'll notice the tap water mix is not the best finish and the river water looks the better of the lot ... even if you use cheapo acrylics.

One artist I knew down in England used the water from his tropical fish tank to mix with.

Conclusion ... fish s**t is the key to successful mixing

That's interesting. I do all sorts of biological filtration for my pond (because our drinking water isn't good enough for fish to live in ! ) So I wonder, how good is that water for thinning my acrylics ??

[Gern]

Conclusion ... fish s**t is the key to successful mixing

I've just ordered that Model Colour thinner from John. P'raps I should have waited and got the missus to bring me a cupful of water from her tropical fish tank!

Gern