Hi ljes,
I don't know much about kitty litter, but you can just use plain old garden/yard dirt for all of them. Be sure to not plant the water lily too deep in your dishpan.
Just pull the marginals out of their little pots and set them into a bigger pot, with a bit of soil in the bottom that brings the plant up to where it was planted in the first pot, then fill soil in around it.
Any container with a few inches of water in it will be fine for holding your marginals, but put the lily in something deeper, like the tote.
I've never used osmocote, but I think you can use it on the marginals too.
Most marginals grow pretty fast, so be sure and use fairly big baskets for them. I usually just use some old plastic pots.
Have fun!

Should I just use plain old top soil from my yard or mix it with the kitty litter? I read somewhere about using kitty litter, but I didn't think any soil was mixed in with it, just straight kitty litter.

For the other 3, the baskets are 9". They are crowded in little 4" pots right now. The baskets have tiny holes all over the sides and bottom. If I use plain top soil from my yard, do I have to worry about the soil coming out of those little holes and polluting the water? The pea gravel keeps the soil from washing off the top surface, right? But what about through the holes? Are the holes so tiny that the soil doesn't come through?

I've never used kitty litter either, but I do have some pickerel rush planted in 9" baskets. I just planted them in the pea gravel, nothing else, and placed the baskets in my open-top filter box.

However, for the marginals that are directly in my pond, I use garden soil and plant them in aquatic (no hole) pots. I cover the top with pea gravel to hold the soil down. Garden soil probably will come out through the holes in the baskets, but the clay kitty litter might stay in the basket better. I wouldn't mix them.

I would go ahead and move the marginals into the baskets with the litter, cover the top with the gravel, and set them in the tote. This will give you an idea if it's going to pollute the water. The plants you picked are pretty forgiving, so if you need to alter your potting methods, they should come through it just fine. However, after the initial cloudiness settles, it could be that the litter will be cleaner after that, and will be just fine. Like I said, though, I have no experience with it.

ljes.....the kitty litter will not hurt or help the plants..it is just used as an alernative to gravel because it does not float in water. The plant will grow in kitty litter and gravel, but the will flourish more with some soil around the roots. When I re-pot my plants, I just put them in the new pot with everything from their old pot and if needed I add some clay/sand/soil mixture...then I put about 1/2 inch to 1 inch layer of gravel..to keep the dirt from floating out into the water. This works great if your pots have no holes....not so good if they have holes...the dirt and clay and sand will come out...even with the mesh pots and baskets...the water will get cloudy. Seems like you have the right size pots. Get some PondTabs and put them right next to the roots of the plants when repotting. The tote will be fine for the lilies...just put it sun light, lilies like lots of sun. For the other 3 plants...if you pots have holes just set the pots in about 1 inch of water...this will work temporarily. If the pots do not have holes, just fill the pots with water every day until you get the pond setup. As long as the roots have consatant water they will be fine.

Amanda

Oh yeah...ljes...forgot to say one thing. Good luck with the new found hobby. Be carefull what you get yourself into. You will start with a small 100 gallon pond, and in a year or two we will see you on here posting about building a bigger pond :) It is an addiction, starts small for all of us.

My pets drink the water in my little pond, so what do I do about fertilizer?

Hi
IME most water plants will grow in anything including nothing at all. So the only real question is what performs best in your situation.
For me kitty litter has the least drawbacks except for the necessary repotting.
Have recently switched to "Turface" a type of heat treated clay material. So far it's runaway the best material I've tried. Might also suggest "Oil dri" as opposed to litter much higher quality clay. Decomposes much slower..
You could also go for "Aquatic plant soil" such as Schultz. Only thing I've got against it is the price but in small quantities ?? gary