Are grow tents worth it? or should I build my own? I was loking at these High Tech Garden Supply 20" X 36" X 64" GROW TENT that's over 32 cubic feet of Grow Space! Same Top Quality Grow Tent as seen elsewhere for much less money than what all the others are charging. This unit is a perfect size for 250 or 400 watt grow light. $149.99 <more> But I could always build my own Has anyone here built one?