Originally Posted by pglenn
OK, so then no pre-determined time as to when to add CO2 to the tank?
Malkore (above) pointed you to a link with a CO2 chart that will tell you when you need to add CO2. You need to measure your ph and kh in order to calculate it.
CO2 on its own isn't going to make a huge difference to your plants, though. CO2 has to go hand-in-hand with lighting in order for the plants to be able to utilize it. So as long as you've only got 20w, there's really no point adding it. Even if you add another 20w bulb, you'll still be under 2wpg, which is still considered low light.
If you've decided you really want to go the planted
tank route (and it sounds like you have), you should look into upgrading your lighting to a 55w or 65w compact flourescent. If your lights are fixed in a canopy, you can get a retrofit kit from ahsupply
, among other places. Otherwise, you could check lights and prices at big al's
For more information, Rex (who posted above) has a good information section on his website. It explains this and many other things you will need to know.
Oh, and for a replacement for the acorus, it's really up to you. Check out here
. You can choose a plant to match your layout and your light.
Keep us posted.