Introduction

Welcome captj. There is lots of good advice here on DB, yet I have to say that I would listen to none of it until I took a proper freediving course. Have a look at F.I.I. Freediving Instructors International - from the beginner to the instructor . I highly recommend it. You won't find him posting here, 100% hands on.
Dive safe...
Tony

Hello Capj nice to have you here hope you will be able to achieve what your looking for... All you have to do is to use the search for breath holding and you will find many threads about it...

All best

Hi Captj, welcome to DB. You will find it a wonderland of great information. Tony has a point though. It is often hard, especially for a new guy, to separate out what will work for you from the huge mass of information here. Since you are close to two of the best courses available, FII and PFI, take a course. It may look pricy, but, if you are a serious diver, it will be the best $ you ever spent. Once you have done that, you will have the knowledge base to interpret and get the most possible benefit from what you find here.

Put it another way, it will save your ass. 100 ft spearing is serious depth. IMHO, you can't learn to do that SAFELY with what you can learn on the internet. One of my deeper diving buddies and I had taught ourselves how to dive in the 30 meter range before I took the PFI course. Never the less, that buddy is alive today today entirely because of what the PFI taught me. (and the two of us are headed to the Bahamas for 8 days of diving starting Saturday, YEH!)

Good luck and dive safe.

Connor

Welcome from Texas! Yes safety is the prime focus. Personal best time or depth all fade away if YOU don't come up whole. I cheer you on in your venture!