We used 3 1000 watt bulbs over an 8'x4' plastic lined plywood tray. Ebb and flow. Clones in the closet under fluorescent bulbs. 64 ladies in the tray in pots filled with lava rock. Plenty of air circulation. No added CO2 but we spent hours and hours in the garden working and breathing so that mitigated much need for supplemental gasses. No pests to speak of human or otherwise.

It was beautiful! Did that for two years and eventually moved on. It's real honest work and if done with the appropriate level of discretion and attention to detail cultivation can be extremely rewarding.

I realize this is now off-topic but it's worth knowing especially for those thinking of using an aquarium. It's not a good choice. I'm unfamiliar with the gpw abbreviation. Clarification please. Thanks.