Never put 0 on minimum delay because you can't go below 500 (+/- 20) on HGSS or 600 (+/- 20) on DPPt. So you should start the search at the proper minimum delay. I never search with 0 on maximum either, because PokeRNG gives you the first seed it finds, which will be a seed under 1000 if you start with a minimum delay of 500. I do searches from 500 to 1000, 1000 to 1500, 1500 to 2000, etc. You will discover that the same IV spread will occur on different delays, sometimes with better frames, if you do searches like that.