Aside from moss, I saw some pictures of aquariums with small thin grass and tiny-clover like plants on the bottom. Both would create a dense bedding on the bottom of the aquarium.

Do you know any plants like that? if so, do they require special conditions to grow, unlike moss.

well there's dwarf hairgrass, microsword and dwarf baby tears. The hairgrass I haven't any experience with but I've managed to get microsword to grow in <1wpg conditions with no ferts or co2. It takes forever but its growing.

I have dwarf baby tears in my new 30gal (roughly 2.5wpg) but unfortunately have developed a huge brush algae problem which is causing all the lower leaves to rot and only the new exposed growth to grow until it becomes covered with more algae... Hopefully I'll get some amanos this week at $9 an invert. What a rip. Not even sure if they'll take care of the brush algae. They wiped out the hair algae in my 16gal.

Anyway my point: The two above mentioned make nice cover and will grow fast with 3wpg co2 and ferts supplied. There aren't too many ground covers other than moss that will grow quickly and healthy without it.

I have brush algae in my tanks and it's growing too fast in my 100 gallon becasuse I need to do a gravel clean (I use huge powerheads with an undergravel filter) and change 2/3rds of the water. With lower nutrients and a non acidic condition I've had this algae stop growing, or at least hardly grow at all.

Check out www.plantgeek.com under algae. Scrole down to the brush algae and look at the pic that looks like a flower.

I kind of like it when it's covering areas of wood because it looks like cm long velvet and it ripples in the current. It's just now that there's too much nutrient in the water it's taking over the plant leaves as is your problem.

I think a product called Phosguard works pretty well, but it's basically the excess nutrient level and maybe pH 6. somthing or less that causes it to be a problem.