If your water parameters are good, then I would recommend just leaving it be. But sometimes when the fish grows bigger or we add more stock, there is a limit how fast the bacteria could replenish enough to do their job...
I see. Thank you. I think I view and do things a bit differently here. Once there is a properly sized and properly aerated and established biofilter in a system, I think there is always, at all times, a small fraction of BB's floating in the water column (less than 1% of overall amount), so adding more of bottled (dormant by the way) BB's won't make much, or likely any, difference in the seeding speed of new colonies. The seeding speed will be the same and (in first approximation) only a subject to the available concentration of the BB food, which is ammonia and nitrite.
More food (along with more oxygen and more surface area, which we assume in our example to remain constant) encourages BB growth. BB colonies seed and grow 1000x faster than fish grow. So in the properly set up filter that has a good amount of reserves, the fish stock slowly growing cannot be an issue.
Now a sudden increase in the bioload, as in the addition of more fish, can increase the ammonia and nitrite concentration to the point that the filter is not coping and these toxins appear more than zero on our water tests. But again, I believe there is plenty of BB's already floating in the water column waiting exactly for this moment, for this occurrence of more food becoming available, giving them a chance at settling and growing.
... Infrequent WC schedule, leftover food or waste that accumulates in the substrate could sometimes overload the filtration IMHO.
The poor maintenance you mention of course cannot at all be counterbalanced by simply adding bottled BBs, I think you'd agree with that.
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Overall, BB biology is quite complex and not entirely studied yet. For one instance, the BB's acting and thriving at high ammonia of say over 4-6 ppm differ biologically from the ones that take on the main role at lower ammonia. They are different microbial species, I guess. So huge spikes in ammonia is a whole another can of worms which is even harder to rationalize. Who knows what else we don't know about these critters and their humble and quiet tinkering behind the scenes, which enables our enjoyment of the hobby
$0.02
Those who know more, by all means correct me and school me, please.
