Hello, i have a ten gallon tank with a docile betta and a mystery snail. The tank is next to a window. Right now i have an amazon sword in there and want to get some dwarf hairgrass. Will i need any extra lighting if the tank is next to a window? What is a good D.I.Y way to increase Co2 for the plants? stupid question but can "too much" Co2 hurt the fish? Any other tips will help! Thank You!