I have a 55 gallon tank with about 10 plants in it 10 zebra danio (for now), lyretail swordtail and a bushy nose pleco and I plan to add a rainbow shark and something else. Anyway I have 2 T8 lights on for about 10 hours a day filter always running and a powerhead (Marineland Maxi-Jet 600) always running. I just got a Fluval CO2 kit for up to 40 gallons really cheap (comes with gauge, counter and diffuser). I also got a CO2 monitor thing that says the CO2 is low.Here are my questions: Will the CO2 be okay to add even though it says up to 40 gallons? I imagine it is better thank nothing. Another thing with this is it doesn't have a solenoid so should I manually turn it off at night with the lights and turn on air bubbles and how many? Also should I install the diffuser below the powerhead intake ideally? Should I keep the powerhead on all the time? I'm not sure if there are dead zones other than above the powerhead. I also imagine keeping it on at night would help with aeration with the CO2 installed. I heard I should take out the mechanical/chemical filter from my tetra filter unless the tank looks dirty and this will help the plants. True or False? Note:I also got some super cheap blue and white LEDs I'm going to replace the T8 with. I can use the T8 on a smaller tank. Thanks for any help!