Gratz on first water change!! When I asked about the bulb I meant MH or HPS but I see from photo I could have answered my own question and I apologize for not being clearer. I also run a 400w cooltube in my tent and I'm thinking you can drop that light down to about 12" above tallest plant but dont just drop and ignore, drop then check after awhile. Gonna see if I have a pic of my light when they were little.

The pics I found were not exactly what I wanted to show but will get the point across. Those are my 4' floros that were used in the basement back when they were lil and you can see how low the lights are. You want to get the light as close as possible without burning plants. It's a fun lil game you get to play with plants, you get to raise the light a lil every week!! One last thing, save some pennies and pickup an MH bulb for veg next time. Can be bought at home dePOT or Lowes for around $25. :thumbsup: