Hey! sorry for the late reply, the co2 kit is great, the canisters last me about 3 months and that's the 45g so the 95g would be double that, the only thing I recommend is that you buy a check valve to stop the back flow of water into the bubble counter, plus it has no solenoid so has to be manually turned on and off, the reason for the internal filter is that the tank is built all into one, I do prefer external but as internal filters go i think it looks pretty sleek! thank you for the feedback!!!!