My budget is super slim and it would probably take at least 6-8 months to save up the money for the Direct Injection method.
You can use DIY CO2 for a bit to see whether or not you want to make the dive into pressurized CO2.
However, as you are already aware, DIY CO2 may not be the most effective way to get CO2 into an aquarium that size.
I am going to get some Flourish Excel and at least start that process to help. It has to be better than nothing. Also is there a way to measure the amount of CO2 in the water?
Flourish Excel will work as well, but again, is less economical than CO2.
As Excel is not carbon dioxide (and is a carbon dioxide alternative), there is no way to measure its presence via a drop checker.
From the algae guides I have seen it appears that I have Blue Green Algae although it apparently is not an actual algae but a cyanobacteria. I know that you know that, I am just double checking because I am hearing folks say they have BBA and I am not sure what kind of algae that is.
BBA is black brush algae, a different type of algae.
The algae is a dark hunter green with an odd blue tint that is slimy and stringy at the same time. I have also read that it is toxic so I have been hesitant to just wipe it off the glass and now it is on some plants.
This sounds like the hallmark of blue green algae (cyanobacteria). It is slightly toxic (i.e. if ingested by fish) this is why most fish do not bother picking at it.
You can remove it manually with no problem (though it may come back very rapidly unless the root cause is addressed).
I did read the part about spot treating with Excel and I am going to try that.
I am not sure if Excel treatment on BGA will help; it is generally used for BBA.
I certainly hope this is not too much to ask, obviously you really know your stuff!
Are you a chem professor by chance?
No, I only have a chemistry minor (I have a Master in Microbiology and Immunology and work as a research associate)