Originally Posted by sam7152004
I would like to add CO2 to my tank to enhance plant growth. My plants started out fine, but as they grew they started to look kind of yellowish. Not unhealthylooking, but not florishing. I use vitamins twice a week so the only thing I can think of that I might be lacking is CO2.
There can be many different things causing this, so we need to explore each and find the problem(s). At the end, You might be able to resolve them with little or no expense.
First, tell us about your light. Please be specific. Is it fluorescent tube, or incandescent (screw-in bulb), and how many tubes/bulbs? What is the description of the tube/bulbs (wattage, kelvin, name, manufacturer). How long is the light on each day?
You mention vitamins, from which I assume some sort of plant fertilizer. Which product, and how much and how often do you add it?
Last, what type of plants? While many plants manage in varying conditions, some need more light, some more nutrients, etc. Combining plants that have similar requirements and when these are what you have available, you will be more likely of success. And how long has this tank been set up? New plants frequently lose their leaves as new ones grow. But I can't say that is the issue until I know all the above.