I left for three months and the tank went downhill. Algae galore. I think it could have been prevented if I would have kept the CO2 going, since the plants STOPPED growing and the algae took over. The plants didn't die, but their growth was stagnant to say the least. I've decided to start again from scratch, aquascape-wise that is. I'll still use the same tank and filter and whatnot. I'm just going to move out the shrimp and fish, empty the tank and clean it, put new dirt in, cap it, plant and arrange it, and release the aquatic dudes into their new pad. I'm hoping that there won't be too drastic "cycle" spikes since I'll be using the same filter. We'll see though.