Let me try to address a recurring question - "but Prime saved my fish from an ammonia event?"
Let me give a brief (haha) run-down of some reasons why a hobbyist might think that Prime etc has saved their livestock from ammonia when it hasn't. (No judgment, less than a year ago, I had some fish loss and not much time, detected a little ammonia, and dosed Prime to "save" the unaffected fish. I was convinced it had worked. Here's why I was wrong.)
1. Ammonia accumulates more slowly than we think. When I feed generously for my small fish, (pinch of flake + cube of mysis + cube of brine) I am only putting in enough protein to elevate total ammonia by 0.5 ppm.
If I feed a cube of mysis, a cube of brine, and a pinch of flake...
mysis: 3.3g x 7.6% protein x 16% N in protein = 40mg N
brine: 3.3g x 3.7% protein x 16% N in protein = 20mg N
pinch of flake: 0.5g x 53% protein x 16% N in protein = 42mg N
Total = input of 40+20+42 = 102mg N in 260L system = 0.39 mg/L of N
if 100% of that protein N went into NH4 that'd give 0.39 x (18 mass NH4 / 14 mass N) = 0.50 ppm NH3+4
Since fish release ~80% of protein input as ammonia, this would take 5 days to reach 2ppm ammonia. If you feed sparingly, you could probably stretch that out to 2 weeks before total ammonia would go up to 2 ppm, even if your tank consumed zero.
2. Most ammonia is non-toxic NH4. NH3 is a small %. pH really matters. Even if I have the hypothetical 2ppm total ammonia at pH 8.2, then it's only 0.13ppm toxic NH3. see
calculator. If the pH drops to 7.8 then 2ppm total ammonia is only 0.05ppm NH3.
3. Most organisms are tougher than the few sensitive fish we think about. From RHF
article
" Marine fish generally have 96 h LC50 levels that range from about 0.09 to 3.35 ppm NH3-N."
That is, while there are sensitive fish that have a LC50 (lethal concentration to 50% of specimens) over 4 days (96 hr) of ~ 0.1ppm NH3, many saltwater fish are much tougher. So many systems could spend days at the above hypothetical 2ppm total ammonia (pH 8.2, NH3 = 0.13) and not lose livestock. Benthic organisms are even tougher than that, in looking up NH3 tolerances for random inverts in my system, pods, asterinas, snails, crabs, shrimp - all quite high by our sensibilities.
4. We assume new fish will be a little stressed in a new environment "take a few days to settle down." Many hobbyists might confuse some sub-lethal level of NH3-stress for new to a system stress, and think Prime prevented NH3 toxicity.
5. Any non-frozen bottle of traditional nitrifying bacteria can keep up with a slow rise in ammonia laid out the scenario in numbers 1 and 2. Recommended dose of Biospira can eat ~0.5ppm ammonia/day straight out of the bottle (for me anyway). One and Only a little slower, Fritz turbostart a bit faster. They expand capacity quite well too, especially if there is a constant presence of ammonia.
6. Heterotrophic bacteria are everywhere (and in some bottled tank starter products). They can reproduce really fast if conditions are right. With addition of carbon - present in all fish food - they can process ammonia quickly also. Plenty fast to avoid bad outcomes. Bottled bacteria myth or fact thread showed repeatedly the
headscratching result that
adding fish food caused ammonia to go
down with these bacteria.
7. There are a zillion photosynthetic organisms that will show up rapidly in any tank that has light. Photosynthetic organism are strong consumers of ammonia themselves, and they release dissolved organic carbon that can help the heterotrophs consume ammonia also.
8. Photosynthetic organisms have such a strong preference for ammonia, that they have a hard time consuming any other form of N, if any ammonia is present. They'll ignore 20ppm NO3 to grab 0.2ppm ammonia. It's not like they are choosing it, it's just so much more energetically favorable as a food source.
9 / Putting it all together.
Tank "crashes" / die-offs don't raise NH3 as much as you might think. A 100g of dead fish that hides in your 55 gal (210 Liter) tank doesn't immediately turn into a bunch of ammonia. The fish might be ~20% protein, ~16% of protein is N, so 100*.20*.16 = 3.2g N. 3200mg N / 210 Liters = 15mg/L N = ~19 ppm total ammonia
Protein is broken down gradually over days to a week so maybe only 3ppm ammonia release per day. Some of that is eaten by clean up crew, that might assimilate 20% into growth and release the other 80% as ammonia. The carbon in the tissues also increases heterotroph activity that reduces how much N is released into ammonia. And on top of that, the metabolic processes involved in breaking down the fish will lower pH as well, thus reducing the fraction of ammonia that is NH3.
If all that decomposing organic material pushes the pH down to say 7.8 (my tank goes that low sometimes without dead fish), then the daily 3ppm total ammonia release would be only 0.08ppm NH3.
And that's without even considering the nitrifiers and the photosynthesizers, that with ammonia present will do nothing
but eat ammonia, day and night.
So when I lost a couple of small fish to rapid disease and added Prime to "protect" the rest from toxic ammonia, there was never actually a clearly toxic condition to protect them from.
If I wanted to do something I could be sure would help protect fish during an ammonia event:
1) lower pH (7.8 is fine in a pinch, I wouldn't try to push the aragonite buffer around ~7.6)
2) add algae
3) add carbon (vinegar or whatever carbon you already use in your system)
4) add aeration (heterotrophs and nitrifiers both need O2 to work well, and the die-off could push O2 low.)
edit: 5) and y'know... water changes
Those are all incontrovertible and do not require trusting any unsupported manufacturer claims.
