It doesn't cost him anything, he also has a 15,000Gallon. He's on well water, and he drains them via swimming pool drains and overflows to ponds in his yard (if they weren't a pond before, they will be when you dump 10,000 gallons of water into a hole). It also says he has over 100 other tanks in his house and he was "removing" 60 or so and still had a lot. His total water changes per week are around 20,000Gal. Very interesting read if you read through the thread.
Also, quite the accomplishment for someone who is paralyzed fron the armpits down.
120 Gal SW, 150lbs Prem. Fiji, 23Gal Sump, 2x250w 15K MH, 4x65w Actinic
3 x Halichoeres Chrysus (1 surfed), 3 x Nemateleotris magnifica, 1 x Centropyge bicolor, 11 x Scarlet Hermits, 6 x Zebra Hermits, 40 x Astrea Snails, 6 x Nassarius Snails, 3 x Cerith Snails