One Time Flush?

Okay so long story but I am 8.5 weeks into flower, getting ready to flush the shit outta these ladies and harvest! :thumbsup: Here's the long story, for one reason or another, I don't have a table in there. I went to the store and bought some corregated roof, and wood, so I can technically build a table in there anytime. However, I really preferred to do so *after* this first run as the room will be empty. I vegged for a tad too long, so I don't want to be moving the plants around real often however I am toying with the idea of doing the flushing in the bathroom. However, like I said, I don't want to move them in and out a ton of times. Would a one time 20 gallon flush per plant do the trick? I would also be using Clearex FYI. I could *maybe* do two flushes, but as I've said... it's crowded in there and it's a pain in the ass to move them frequently (they get a little tangled and such) Anyhow, curious to hear what you guys think about this idea?