i have two tanks that are about to finish their nitrogen cycles, now i have
high nitrates. i have a few plants (two types) but i have no idea what they
are, i had got them because 1.) i heard they would help with the cycling and
2.) to give the fish something to nibble on.

my tap source water is 0 ppm nitrate.

15 gal (US):
ammonia 0 ppm
nitrite .25 ppm
nitrate 80-160 ppm
pH 7.4
temp 78 (F)
population;
1 med angelfish
1 neon dwarf gourami
1 sunset platy
3 african dwarf frogs

20 gal (US):
ammonia 0 ppm
nitrite .25 ppm
nitrate 40 ppm
pH 7.4
temp 80 (F)
population;
3 green tiger barbs
1 fire sunset platy
2 african dwarf frogs

the plants i have in there now *seem* to be doing fine, (they are growing)
one is a floating viney type plant with a multitude of blade type leaves
that come directly off the stem, each plant is a single stem that has grown
to about 12-14 inches (36-40 cm) with 3 stems floating in each tank. the
other plant is set into my substrate of the 15 gal. and has multiple stems
with small 1/4 inch (1 cm) broad leaves. this one seems to have *roots*
growing out at places where the stems diverge. height is apx 6 inches (15
cm).

what is the best "beginners" plants to have and where should i read up for
more information, and what is the best way to control nitrogen levels.

TIA,
tedd.