The thing is, noboby wants to hear that everything is OK. Instead, they want to tell you it will be a crisis/disaster/etc., because that makes them feel important and relevant. For example, I just took this photo while watching TV in the living room...
There he is, doing pretty much the same thing he does every day, and like he has done for the past 3&1/2 years. To be totally honest, the tank is long overdue for a water change, I haven't scrubbed the algae in a while, need to trim the plants and vacuum the gravel, etc. I could be better about the water changes but life has just been really busy for us lately so mostly, I just top off the tank when it needs it, change the pads in the wet/dry, and feed the guys every day. And guess what? He is as healthy as ever. So, if someone asks me if Mbu are easy to keep, I say,
"Sure, just make sure you have a big enough tank, can get the right kind of food, be selective with the tankmates, and they do great". But, nobody wants to hear that because while it might be true, it is boring. And things which are boring don't rally people to respond.
Now, say, for example, some "scientist" or "mentor" gets asked the same question, but they respond with a strongly cautionary statement that you must have a 1,000-gallon aquarium, some sort of filtration system that sounds like belongs in a sewage treatment plant, and that it will be nearly impossible to keep water quality up for these guys, "or else", the listener says,
"Whoa, you are really an expert! Thanks so much for loking out for me and for the fish. I'm going to listen to you from now, on!" And presto, they now have power over someone because human beings make decisions based upon emotion and then invent rationale to defend those decisions.
So, while I might tell someone that Mbu, in my experience, are one of the
easier fish I have kept (keeping in mind that I have the space and food for him...) that is neither exciting nor controversial, so it does not compel people to listen. But the minute you create emotion, for example, by taking a cautionary tone with every statement or invoking the "pet's best interest" in replies, you are now forcing the listener to either submit or to leave the conversation.
"It's not about me, it's about the fish/ I'm a scientist, so know more than you/ The mentor said it so it must be true". This is actually a pretty common thing in internet forums, across the board.
Getting back to the Mbu, I just measured ours and he is 26"-27" long. He eats 3-4 adult crayfish per day and his growth appears to have slowed down during the last year or so. This leads me to believe that he is at or very near adult size. Obviously, he will continue to grow throughout his life but at a greatly reduced rate. I can tell you that the size tank we have him in, 72" x 36" seems to me like pretty much the minimum footprint for an adult of this species. Obviously, bigger is better but they
WILL do fine in a 300-gallon of this dimension.
In regards to filtration, I have seen zero indication that this species is anywhere near the Godzilla-type bio-load that often gets tossed around. Yes, they poop like a dog and I just net those out but honestly, the last time I did a water change was a month ago and aside from some yellowing of the water, the fish are doing great. I do want to point out that we have a pretty good population of Pothos and Peace Lilly growing out the top the tank, which I am sure is helping with the water quality. I recommend the "plant filtration"-thing to anyone who is keeping big fish or heavily stocked tanks. Other than that, just a wet/dry sump of about 50 gallons volume and a canister filter which I use for activated carbon. Basically, same type of setup you would use for any 300-gallon tank full of fish.
Anyway, just my observations in keeping this guy.
