Would Flourish Excel work as good as a CO2 setup?Neither, those are 1 liter tanks and apparently are not even pressurized to normal levels. They are way too small for a 75 gallon tank and can be hard to refill. You should buy a proper 10 lb or 5 kg co2 tank compatible with whomever you are refilling it with and get a real 2 stage regulator with solenoid etc.
Another question although on a tangent. I can’t use my tap water for my tank due to the salt content and I can’t find enough distilled water. Is reverse osmosis water fine for a planted aquarium provided that I add the right nutrients?excel will cost you a fortune in a 75 gallon tank. You will be going through a gallon or 2 a month, without getting the results you want.
Save up and get co2, and a good light. You will be much happier with the results.
All of those but Hemianthus are easy to grow plants with the exception of hemianthus. They will all grow in a low tech tank without co2. HOWEVER, they will not carpet quickly. And by not quickly, I mean years instead of weeks or months. As others have said dumping excel in will not let you grow plants quicker or let you grow a plant you otherwise couldn't like hemianthus.That’s good to know. In the event of using Excel though would Helanium, Mersilea, Hemianthus and Eleocharis be safe with it? I’ve heard of it melting mosses but these are all carpet plants.