To Compost or Not to Compost

I am just finished making my new pond and an now considering starting to
move my plants into it. Currently they are potted in baskets with
aquatic compost. But this tends to leach out and gather on the bottom of
the pond. I was wondering if I can plant my plants just into pea single
and they will still do ok. I have several water lilies and some water
hawthorn.

thanks

Paul