Re-Seeding Nitrifying Bacteria from Main to Frag Tank.

[Azedenkae]

Ok I may very well be off in my hypothesis but I’m trying to figure it out. So thinking that maybe the macros grew to the point where 100% of ammonia and nitrates were absorbed by it, starving out the nitrifying bacteria, it all dies and ammonia production in my tank grows beyond what the macros can handle and now there’s no more bacteria to breakdown the excess and so it builds. I really don’t know and am confused by this whole scenario. Yes I use API kits. I just know that I have no nitrate and I do show ammonia and unhappy corals, which is why I’m thinking I killed my cycling bacteria somehow.

@Dan_P I think this may be a reasonable explanation. Unlike nitrifiers that utilize ammonia as an energy source, which can keep on going even if the growth/population of the nitrifiers stagnate, macroalgae would utilize ammonia as a nitrogen source to a certain point, then if they are otherwise nutrient-starved (less so carbon sources but more so other chemicals), then their growth just stagnates and they don't really uptake ammonia anymore.

There's a lot of factors that go into this though, including that if there is a continuous introduction of nutrients (i.e. by feeding), then there should still be growth no matter what, and thus nitrogen uptake. Nitrifiers also don't just keel over and die instantly the moment they are outcompeted for nutrients (ammonia), rather they can just survive for months or more on end, and then returning from dormancy soon after. Soon enough that maybe there is an initial uptick in ammonia, but that should have been handled.

So I will say I am not 100% sure what is going on here either. It is also possible that there was never enough biomedia for nitrifiers to start with, at least for how much coral there currently is. Did you increase feeding or anything like that?

Also, did you mean you have 6x MarinePure blocks or spheres in your refugium?

 

[Coral Winslow]

@Dan_P I think this may be a reasonable explanation. Unlike nitrifiers that utilize ammonia as an energy source, which can keep on going even if the growth/population of the nitrifiers stagnate, macroalgae would utilize ammonia as a nitrogen source to a certain point, then if they are otherwise nutrient-starved (less so carbon sources but more so other chemicals), then their growth just stagnates and they don't really uptake ammonia anymore.

There's a lot of factors that go into this though, including that if there is a continuous introduction of nutrients (i.e. by feeding), then there should still be growth no matter what, and thus nitrogen uptake. Nitrifiers also don't just keel over and die instantly the moment they are outcompeted for nutrients (ammonia), rather they can just survive for months or more on end, and then returning from dormancy soon after. Soon enough that maybe there is an initial uptick in ammonia, but that should have been handled.

So I will say I am not 100% sure what is going on here either. It is also possible that there was never enough biomedia for nitrifiers to start with, at least for how much coral there currently is. Did you increase feeding or anything like that?

Also, did you mean you have 6x MarinePure blocks or spheres in your refugium?

Yes I have 8 cubes in the display (7 now that I have one in my main tank collecting seed bacteria), and 6 in the refugium section of the AIO. I did start feeding more when I saw the dinos to try and raise the nutrients but that was already after things were going downhill. I did start dosing Phytoplankton (two strains 60 ml combined) daily about 3-4 months ago but that didn’t show anything but positive results. Just clueless here.

 

[Dan_P]

Ok I may very well be off in my hypothesis but I’m trying to figure it out. So thinking that maybe the macros grew to the point where 100% of ammonia and nitrates were absorbed by it, starving out the nitrifying bacteria, it all dies and ammonia production in my tank grows beyond what the macros can handle and now there’s no more bacteria to breakdown the excess and so it builds. I really don’t know and am confused by this whole scenario. Yes I use API kits. I just know that I have no nitrate and I do show ammonia and unhappy corals, which is why I’m thinking I killed my cycling bacteria somehow.

Finally, I understand OK, here are some thoughts.

Bacteria are very resilient organisms. I would guess starving out all the ammonia oxidizing bacteria in a system is highly unlikely. Reducing the population? Maybe, but as soon as the ammonia started to increase the population increase would not be far behind.

For argument sake, let’s say that the AOB died out. Then why did the algae in the refugium not consume the ammonia?

There seems to be little chance that an ammonia spike occurred in your system. The API test for total ammonia when modified is a very good test, but following the instructions, the test results can be visually confusing. So, I am going to provisionally claim, the API test results were misleading.

My hypothesis is that your frags started to decline weeks ago and the cumulative symptoms became noticeable only recently to you. I wiil also stick to the hypothesis of nutrient depletion by the macro algae as the event that led to the gradual decline of the coral frags.

Dan

 

[brandon429]

Very nice summary of likely order of ops



this tank still looks just great, corals rebounded nicely if this above was recent

 

[Coral Winslow]

Very nice summary of likely order of ops



this tank still looks just great, corals rebounded nicely if this above was recent

This is current, this is after the water change this morning. The softies and a couple Acans stayed, the sps I had to move and hopefully don’t loose them. This still isn’t close to what they looked like a couple weeks ago but they’re not closed up either. I think I’m going to just give my cube in the main display a week then transfer it back to the frag tank. In the meantime, daily water changes.