I've been running a low-tech 10 gallon since March and things have gone pretty well, even though I'm a noobie. It's stocked with 3 honey gouramis and 7 celestial pearl danios and other than my own thoughts that putting the CPDs in a 10 gallon was not great, the fish seem fine.
The aquarium's pretty green - there's a ton Hydrocotyle at the top of the tank, and a dark green spinach like plant taking over the bottom of the tank (any ideas as to what it is?). There are also a few sprigs of bacopa, though most of that has not made it since setting up the tank. There's some duck weed at the top and I've been dealing with green algae near the top of the tank.
There are also a couple of small java ferns and an anubias on one side of the tank. They're both rubberbanded to rocks and not buried in the substrate at all. Both are looking a little rough. The java fern has several leaves that are various shades of yellow/brown/black (the largest leaf has a fernlet on it which also is turning black) while some of the anubias leaves have holes in them. The weird thing for me is that other leaves on both plants look great.
I dose 2 to 3 mL of Excel every day (5mL after a water change). I also dose 1/16 teaspoon of KNO3 twice a week and 1/32 teaspoon of KH2PO4 on different days twice a week. I dose with Flourish Equilibrium at 1/8th teaspoon after waterchanges (once 1-2 weeks), and 1 mL of Flourish after each water change. The tank is lit from 11am to 8pm, though gets a little blocked light from a window about 15 feet away.
Images of the two plants are here: http://imgur.com/xb7m751
Any ideas? I'd love to dose whatever the deficiency is but I can't tell.