I'm putting in the liner and rocks next weekend (yeeha! after all summer of
digging and building the waterfalls). Plants will go in as soon as the
water settles [I still have a few growing months left, zone 10].

My local pond store said to put Lillies in half potting soil, half cat
litter. They guy wants to sell me a little bag of 'special' pond soil for
about 15 bucks.

Can I get something at Home Depot or Lowes that I can mix with cat litter
and get same results? Soil from elsewhere in my yard won't work, it's sand
with just about zero organic matter.

Thanks!