No no. Any and all help is much appreciated. Especially given my circumstances.I'll probably be an outlier here, but I think one would be enough. One FX6 is enough to handle the tank, and I know it is super big and messy, but that comes down to tank maintenance as much as filter. Basically, I'd rather clean one FX6 twice as often, as clean two FX6's half as much.
A full FX6 is not light. You can lift and carry one yourself, but I am getting older and lazier. Lugging two out in the driveway to clean out sounds like more work.
If you keep up with tank maintenance, the FX6 will be fine. Keep in mind, that just because you have two, doesn't mean you could be going all that much longer between cleanings. There is no guarantee that the filters are going to pick up half and half. If most of the detritus goes into one filter, you could be cleaning one out of two almost as often.
I had one FX6 with 120g, 2 Red Bay Snook, Convicts, Jewels, Dempseys, and some Clown Loaches. Wasn't bad to me. I wouldn't have bothered with another one (water was crystal clear, but I kept up with vacuuming). Unless you're starting with a full grown one, I'd start with one and just get another if it ever seems like you're falling behind on filtration.
With that said, I have absolutely no idea what I'm talking about and am completely and totally full of crap. So, take all that with a large grain of salt.
And I would actually be starting out with a 12" Piraya not a baby.