[AaronT]

Stargrass doesn't like to be shadowed at all so make sure it's not that. What are your phosphate levels? It might be asking for P.

The tank looks good. I like to balance of color you have going. The only suggestion I have is to let the tall stem plant in the back get taller and bushier if anything to hide the equipment in the tank.

 

[AaronT]

If the plants are starved for P that wouldn't suprise me. Try dosing it to 2 ppm one day and see if it doesn't stabalize at a desired level.