Tuna braid to mono knot

[togzilla]

I have a couple of trips coming up I'm glad they are not until October given the dismal tuna reports. Anyway, after many many years of tuna chunk fishing I'm finally getting tired of working an Intl. 50 all night and want to step down now that some of the smaller reels manufacturers have improved their drag systems. I have several chunking and jigging reels and want to start using my Avet HWX for chunking as I was primarily using it for jigging before. I have 80lb color braid on it and want to put a 100 yard topshot of 80lb. mono. Here's my problem: I have tried tying Alberto's, double unis, yucatan, slim beauty, and sebile knots but they have all pulled out when I draw them tight and put pressure on them. I've watched numerous YouTube videos and tried all of those knots numerous times. I'm using 80lb mono and was wondering if that is just too heavy. What knots are you guys using for 80lb braid to mono?