Yep, same here. I ended up using a sponge filter in my molly tank, and the Frogbit finally stayed put. Bonus: the mollies seem to like the gentler flow too.
plants that pair with mollies
Re: plants that pair with mollies
Re: plants that pair with mollies
Another vote for sponge filters here. They're cheap, easy to clean, and perfect for planted tanks. Plus, no risk of sucking up baby mollies if you end up with fry.