unless you are upgrading to more powerful lights and getting plants that need higher light I wouldn't waist your time.
as for DIY CO2, I hate it, made 4 units and not one worked right. go pressurized if you are going to do it.
just remember that CO2, light and fertilizer (food) are all a balancing act, if you max out 1 of them it won't matter how much of the others you add nothing will change.
for example, if you add CO2 and food, but have low lighting the plant won't have enough energy to utilize the extra CO2 and food, so you will hit a plateau until you increase the light, and so on. the problem I have on mine is food, I can add my home made fertilizer like it is going out of style and can't keep a nitrate level in my tank

heck I can't even grow algae in that tank.. wish my reef worked the same
Steve
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*everything said above is just my opinion, and may or may not reflect the views of this BBS, its Operators, and its Members. If cornered on any “opinion” I post I will totally deny having ever said this in a Court of Law…Unless I am the right one*
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