thanks 4 the comments everyone :-)
@DavidZ - the fry, when they get to about 1 month old, are trasnferred to a BB tank, with high quality filtration, aeration, and 50% daily WC's. i currently have 65 x 2month old fry in there.
@ Fat Guywhen i get some proper plant substrate, i want to get some HC for a carpet. when i get that going there will be less stem plants.
@ Problemman - ambulia is a common LFS plant here in Australia. costs about $5 AU.