The means you probably added a little too much liquid, but they should still work! Hope it worked out for you.

I have hard water as well, but it’s not super hard. You can increase the amount of citric acid to counteract hard water.

While this is true, it doesn’t apply to this recipe if you follow the directions. The way the steps are set up here, the vinegar reacts with the baking soda in the dry ingredients and has already been nullified by the time you add the castile. So it’s not a problem.
Since the baking soda and the vinegar cancel each other out, from what I can tell, the vinegar acts as a way to moisten the dry ingredients into a malleable form without adding water. Which is fine, it worked great. But me personally, I’m kinda lazy, so next time I make this, I’m just going to leave out the baking soda and vinegar and make a powder with everything else, and then use vinegar separately as a rinse aid. I just don’t have the patience to press soap into ice cube trays :)

They’re fairly crumbly but wont like fall apart

I get it on amazon.