Yeah the brown tips are from the soil I was told had way too much fertilizer in it but since I put them in the new soil they have like you said exploded I see 4 new leaves coming in already I'm sure the co2 is helping alot too but now that I have and know everything I need I'm ready for them to grow

I have 3 gallon pots if you think they would be better ? I only have 3 plants going right now but will start germing some more once I feel these ones are taken care of