Disguised weights on aluminum tanks will get caught by the online scuba police. I hear they even can spot those cast lead pie plate weights hidden in a tank boot.
Keep us posted on the developments. (and risk lynching)
Cameron
Haha.. I have been thinking similar 'impure' thoughts. Admittedly, I dive backmount doubles most of the time, but want the option of SM when circumstances benefit from it. I can at least empathize with the OP here.. a little.
My (sidemount) situation is that I have a nice set of HP100s that work great for sm and trim out just fine. But I also have 3 sets of steel 72s that I would also like to use for SM on shorter dives where the HP100s are overkill, or being used by my kids as single tanks..
(stay with me here....)
Using my 5mm wetsuit, and two steel 72s.. I need almost exactly 4lbs of led to be nearly neutral when tanks are down below 1k psi. But the tanks get real floaty in the arse, just like the OP's AL tanks. Since I don't really need the lead on my BC when diving the heavy tanks, and I don't want to have to fool around with weight pouches, I tried just putting two solid 2# on the cam bands. Since I have three sets of 72s, it allows me to have tank stage/bands that are pre-adjusted for both tank types and is pretty easy to deal with.
I have dove these like this twice and did not have any issues. It did seem to solve for the floaty tanks, did not cause any issues with tanks being too heavy, or screwing up trim in the water. I did think about putting lead inside tanks boots, but I am just playing around with this for the time being.
I am not presenting this as a "best practice", or claiming to be another sidemount guru. Just chiming in with what has worked (at least a little), for me.
*I do recognize that my alternative is to put the 4# onto waist or back trim pouches, and use either sliding D-rings or a belly-bungee to keep the tank bottoms down. I may try those options out at some point.