Succesfully Weeding out Breeding Pairs - Peppermints

Been buying up peppermints when ever I could find them at the moment ive got about 10 adult females and 8 adult males give or take one or two im not to sure on. Ive had some in a large 5 foot tank to have one male spawn twice and eggs eaten/kicked. I got this male and a female that looked fat stuck them in a breeding tank and they have produced my first successful spawn of peppermints. Now ive separated the rest into pairs and trios but doesn't seem to be anything happening in the other tanks, going through a fattening up cycle at the moment higher temp 27.5 and a few high protein feeds, less water changes ect and in 2-3 weeks will start dropping temp increasing water changes.
OK so all these peppermints ive bought most likely half have been sold because they are bad breeders or too old so I need to weed these out from the good fish. So thinking it through I devised a plan that maybe good or bad not sure but here goes. Ill set up a 5foot*2foot tank for three males eg have three piles of drift wood with a couple of caves in each and drop in three male peppermints. Separate out some females in a separate tank and keep a good eye on them for any appearing to fatten up become gravid. Catch the gravid female and put her in the man tank and give it 7 days with the usual water changes/temp drop ect. See if any action with any of the males and If I get success catch the male and female for putting in to their own breeding tank them repeat the process. If no luck after say two weeks and another female appears ready swap the females and try again.
What are your thoughts guys?

I dont know what others think but if they are fed right and water is right they will breed BUT there again as I dont keep my plecs just to breed what do I know.

If you're simulating dry/rain season, I'd keep them together. In large tank I don't think I'd be only alfa male breeding and even if so, couple of females can lay the eggs in his cave. You'll know which bred anyway - male will sit on eggs, female will get thin. In my opinion, less interference, the better. Mine breed in community tanks, I don't move them around and there's a spawn every 6 weeks. But same as love L144, I'm not focused on breeding. Btw: there's less food in the end of the dry season.

Yeah, there are 101 different thoughts here and every single one of then will have an example of it working too. If you are trying to weed out the bad breeders then you need to assume that everything else is perfect and that the only reason they are not breeding is because they are too old or just lame (I mean who hates breeding   )

I think your plan will work but you might be introducing a little too much disturbance into the mix, although, in some cases (common bristlenose) that can lead to breeding. Peppermints are a little more timid and therefore need to be treated that little bit more carefully. I would suggest just keeping them in their pairs/trios for a few of your cycles and then swap them around. I would go for a 'cycle' every 2 months to give them time to get into condition. Remember peps move a lot slower than commons in terms of their breeding.

That said, there is nothing wrong with what you are proposing. Might work a treat, if you suspect they are old or whatever then I'd suggest giving it a shot, at least for a bit...whats the worst that could happen...