lol I swear I got the feeling you wanted me to get the K, that's fine however, make life a lot easier. So even with the 600watt you think I should go above 4''? If I do get the 6''+carbon filter, so you think I'll need an active intake? Or just a passive? Like I was saying, with the electronic ballast and high quality light bulb, I'm getting 80% of the lumen output, and I'm keeping the plants under a couple feet, so I won't need major penetration...lol.