Hmm.. so basically you're doing the DIY homemade co2 using yeast, water, and sugar, right? Unfortunately, with DIY co2, sometimes it's just not consistent at all injecting co2, but luckily for you, you have a really small three gallon tank, so DIY co2 I think would be fine IMO. You say you dose micros? Well, you're going to need macros too.. You should look for a dosing schedule like Tom Barr's Estimative Index, using that regime, you will make sure the plants don't ever run out of nutrients. How much excel are you using? Just regular doses, right? Watch out and be careful not to overdose, because it might harm your plants, just a heads-up; and since you are already using DIY co2, it's not really necessary imo. So experiment, make sure your DIY co2 is consistent and working properly, improve water circulation without degassing co2, and get those dry ferts to mix and use. Good luck.
20 gallon - Sulawesi Golden rabbit snails/Japanese Trapdoor snails/RCS/Marbled crayfish tank
55 gallon - Rainbowfish Dutch scape low-tech planted tank
250 gallon - Community Tiger Oscar/Red hook silver dollar/Silver dollars/PB Jack Dempsey/Clown loaches/Tinfoil barb/Roseline sharks/Bala shark Monster fish tank