Nice that I’m not alone with the problem.
Thanks for the tip with the colors, but I could have come on it earlier to ask here.
I have my holiday over next week on monday, then go to crete for 3 weeks.
For the next time this is a very good idea.
I still have very small colored ink sticks, they should work too.
I would only need to take an extra inkstone with me, they have unfortunately weight.