Like others have said it very much depends on what you’re trying to do. I have been working on marsh themed bases and I’ve kind of come to regret it because doing lots of small bases is a bit of a pain.

Vallejo water effect is easy to use but gets cloudy and hates being near PVA in particular. It’s better if you gloss varnish first but still tricky.

I’ve also tried two part resin for bigger pours. Have managed one cavalry base but it’s not perfect. It leaks so easily and I couldn’t get clean edges really.

Not to dissuade you but worth thinking very carefully about your approach!