Swordtails usually get a lot bigger than people realize, especially the male swordtails, usually in the 4-inch range. They are usually sold as two-inch fish in the stores but do get larger. Also, the general rule for swordtails is ONE male per tank and the rest all females.
Platies are great fish, probably my favorite of the main staple livebearers (those being guppies, swordtails, platys, and mollies). Can't relaly go wrong with them.
I have a few platies in a ten gallon tank with a few "Golden Wonder Killies". They get along fine. The killies/panchax stay at the surface of the water nearly 100% of the time while the platies tend to hover in the mid level area of the tank. I don't have anything else in that tank right now, but you might consider a setup like that where you pick a species that stays at the top (panchax species), platies in the middle section, and then something to round out the bottom like Cory cats.
The one thing about Panchax is they are pretty aggressive eaters and so any platies babies you get will most likely be eaten. So don't pick Panchax if you want babies.
On the snail thing, see my article here...
--- On Tue, 10/28/08, Aaron <udyfish@...> wrote:
From: Aaron <udyfish@...>
Subject: [Freshwater Aquariums] 20 Gallon
Date: Tuesday, October 28, 2008, 4:00 AM
Any suggestions on small fish for a 20 gallon tank. I know I want a
couple mickey mouse platies and red swordtails, but other than that I
am not sure. I want fish that don't get any larger than 2 inches. I am
up for suggestions.
I also added plants and I also had snails hatch. I counted 11 snails,
I left 3 snails in my tank.
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