For now I suggest you go to www.bonsai4me.com and use a standard bonsai mix but make sure it doesn't ever dry out. Have you got them in water now?

yes i have them in some water, along with horribly crushed lava rock, chipped up pine bark,dust. I also have a little bit of level sand, nursery blend potting mix ,and organic soil. I was gonna make a new blend consisting of haydite, turface, granate, and pine. Would this work for a cypress, or should I add a little soil into the mix? Also, if I keep a rocky medium, what fertilizer is best recommended for the tree, or any bonsai in the future?

Hi, don't use 'dust' in any mix for any tree anytime as it will clog pores of the roots. I don't know what 'level' sand is (levelling?) but sand per se isn't good either unless it's really larger grit of some kind. Potting mix is usually mostly peat moss, so 'organic' soil (?) would not be needed (or the peat wouldn't). Haydite plus turface plus granite is overkill - either haydite or turface alone is fine, with the pine. A little(read italics there please) coarse soil could be added. Personally I just would use aquarium gravel (small and/or medium) plus bark and maybe a little perlite for almost anything if you know how to water properly, and taxos shouldn't be allowed to dry out of course, but don't need to stand in water full time at all either (they grow all over in 'regular' ground soil). A balanced houseplant fertilizer is fine for most trees most of the time except that conifers need next to no nitrogen in the late summer through winter.

I keep mine in a saucer full of water, in a med-tall pot. I did loose a fine one to drying out. I'm considering completely submerging the pot as these trees don't need air at thier roots.

Wrong! All living plants need 02 regardless of what they grow in, and I think if you submerge the pot, you'll end up with rot of some kind. Do you know many Taxos grow all over the US in the ground, and not in water? You'd be better off, in fact, doing that (or a pot version of it) than drowning it.

Hi
If you grow these in standing water they will develop "knees" I stand the pots in my fish pond,keeping the top of the pot above water. This is one of the most interesting features of the plantIMO gary

They are very nice though . . . they do breath through the 'knees', although they will make the 'knees' on dry land as well (and through slabs, as my sister found out even though it was planted ten feet from the house. Poo.)

If you compare bald cypresses growing on dry land to ones growing at the edge of, or even directly in water, the trees nearest the water have much wider and more tapered trunks and also far more knobby exposed roots. For bonsai a wider trunk is more desirable. My bald cypresses here in Texas sit in a shallow pool of water all summer long and have done wonderfully. I was not very successful at keeping them alive or looking healthy due to the rapid drying out in the extreme climate here without submerging them. I use about a 25% inorganic to 75% organic soil mix for a bald cypress.