If you only need to lose 30 pounds, you could achieve this almost entirely with two lengthy dry fasts. I lost 21 pounds on a 7 day soft dry fast, I have plenty to spare however so your results may be slightly less but similar.
If you’re already used to dry fast, try 36 hours. It seems like 24 if you time it right. I stop eating after dinner, fast through the next day, and then until lunchtime the following day. When I’m not a lump, I do that once weekly. Weight loss depends on my eating properly the rest of the week, too. Seems that 36 hours could be done twice weekly as well.