Firstly I never said that diving sea caves without qualifications is safe - it is not. It is however the case that in the instance of that particular cave I was prepared to accept the level of risk that some consider unacceptable.
Regarding decompression diving I also know that you should be trained and build up to it gradually, not just leap off the boat with two tanks and hope for the best.
However my interest in diving is such that I do not want to spend that amount on training or diving equipment. A basic decompression / technical diving course is not that expensive but the equipment is not available at many of the locations I dive.
More generally if people only did what they had learned from others we would still be living in the stone age or possibly not that advanced.
You continue to contradict yourself. Several people have tried to help you and I very nearly did as well. When I initially saw your thread I began posting a link to (free) PDF’s of the IANTD EAN Diving and Decompression Tables, but after reading your responses it became apparent I would only be providing you with the proverbial rope to hang yourself.
According to you “there are two things that limit time at depth, quantity of gas and NDL”. Unfortunately there are many more irritating little details, especially if you “plan” on diving multiple gasses, like EAD, PPO2, FO2, RMV, GF, OTU’s, PATA and CNS, to name a few, all used in conjunction with formulas, tables and gas calculations for comprehensive dive planning. You said you “would become bored hanging about doing deco stops”, so your objective is to do 50m “max bottom time” wreck dives with 50 to 75 minute run times with NO deco obligations. Is this correct? Furthermore, you intend to do a gas switch to AIR after descending to the MOD of your secondary EAN32 stage bottle after entry. How long does it take you to descend 33m to even make a gas switch worthwhile? Do you own a computer with multi-gas switching functionality or does that violate your “minimal cost and minimal complication” criteria? If you are hellbent, emphasis on bent, take
@runsongas advice and dive EAN28. Per IANTD EAN28 gives you 10 minutes at 45m with a mandatory 3 minute deco stop at 4.5m. Anything longer than 10 minutes requires multiple extended mandatory deco stops.
I realize my observations are harsh, but I am genuinely concerned for your safety and those around you. For the most part, I have been simply reiterating YOUR words. Seriously, please be safe, prudent and smart. Get properly trained, certified and equipped. Moreover, PLEASE DO NOT PUT OTHERS AT RISK!