tank maturation and bacteria

[Linc D]

Hey Eric, I just (belatedly) read your article in the January '03 issue of RK about reef bacteria. I was wondering what your opinion is on the issue of new tank maturation as this relates to bacteria. To use my own example (I admit this is my first reef tank, so please excuse my initial excesses), during the 1st 9 months or so that my reef tank was set up, I had a quite high mortality rate of new additions (both fish and corals) to the tank - maybe 50% (ammonia and nitrites were 0 throughout this period). Since approximately the 9 month mark, however (maybe a little after that), my mortality rate for new additions has dropped to virtually 0%. My impression is that some quite drastic- and beneficial- change occurred in the tank at that time, making the overall system significantly more hospitable to new inhabitants. My assumption is that the critical change that occurred in the tank at that time involved a change in the predominant bacterial populations in the tank (the usual tank parameters – pH, alkalinity, etc, etc did not change significantly at this time). In other words, tank "maturation" – and therefore stabilization - is accomplished via the establishment of certain beneficial predominant bacterial populations, and this typically occurs somewhere between 6 and 12 months after the tank is set up (I am using the term “tank maturation� here quite differently from the “tank cycling� process which occurs during the 1st several months of tank life and during which “nitrifying� bacteria become established). Obviously, if this were true, it would be fascinating to try to determine which bacteria were involved, and if there is any way to facilitate their growth in a new tank. Any thoughts? Linc Duffy

[EricHugo]

Yes, I think that's part of it. The process of succession applies to bacteria, algae, and corals, too. Also, tank water chmistry and its stability and ability to support life involves far more than just nitrogen containing things. We measure that ammonia/nitrite thing because it is the most directly measurable indication of the ability of a tank to support fish life, but that's our limitation, not because its the only important aspect. As for bacterial successions, I'm not sure how you could speed up the process, what species of the many would be critical or even involved, or the time frames. Nor am I sure hurrying it would ultimately be good. Patience is a trait that should be welcomed, you know?

[Linc D]

Well, even if we had no interest in hurrying things up, it would be interesting just to know what the critical changes (in predominant bacterial population, or whatever) were. Linc