Just gonna chime in on the photography thing...
I don't want to "shoot it down" as an idea...but it does need a full meeting or multiple classes/sessions to cover the topic. Even for those with years/decades of experience with their cameras who may be regarded as semi-professional photographers...photographing reef tanks is an entirely different animal. There are basics such as reducing/eliminating flow and aperture settings that work...but the bigger issue is always white balance. Unfortunately, adjusting white balance is going to be different for every camera and every tank.
It's something that would be feasible for a meeting dedicated to photography where everyone can bring their cameras and ask questions...and maybe even follow-up with a 2nd meeting/session on post processing. There's just so many nuances to taking the photos and a large spread of experience within the club that cramming a class into a 30 minute session would almost be a disservice.
In college I spent hours a day in the darkroom, and shot literally 100s of portraits with everything from film DSLRs to large format cameras. I was able to do that after taking 1.5 years of photography classes...and am still left scratching my head at times on photographing some tanks (especially under LEDs). I'd be willing to help out with a "photography class", but am by no means a professional photographer, or a teacher lol. I honestly look at my reef pics and think they look like poop at times...and want to blame my 8 year old 10MP camera...but in all honesty it just takes A LOT of time and experimentation to get impressive pics from our tanks.
Definitely willing to help by teaching the basics...but can't promise to impress