I need to start flowering

[HPS]

Hey man. I followed your advice on the 11 plt garden. But I got a little creative, and I dont think it was a mistake. I built a 4 bottle garden, planted 4/bottle to ensure I got plants, ended up getting 16 plants and they are all doing fine in a 2'/2' space, 5' tall. I also have them so close, the bottles are touching. I have not seen any stretching, just some thick-ass stems, and bushy-ass pot 'bushes'! To get them bushy I have been training the stems to grow in a spiral upwards- really cool looking. My problem is I need to start flowering, and I cant afford the hps right now, so I need to slow down growth w/out affecting potency???Do I just take them off 24/hr lights and give them a break, (18 on 6 off) and ease up on the nutrients? Im not sure and Im not going to do anything w/out advice. They are about 15" tall and growing faster every day.