Where do you think I got that giant bunch of foxtail/hornwart & so forth.
I don't buy them because will eat the leaves like candy. Also the fish love the little critters that hide amongst the leaves. I always give them a good soak/rinse outside and water the plants with the water, but there's always plenty that still cling on.
The bettas I'm more careful with what I give them.
Once a plant has been thoroughly cleaned by the fish for a couple weeks, I move the plants to other tanks or where I feel they're needed.