Gutloading bacteria

[reefluvrr]

Hi @Kenneth Wingerter .

I would like your expert opinion if I can gutload bacteria such as live PNS Probio?

After reading a thread in the forum, there is a user using bacteria mixed with amino acids with acetic acid carbon source, trace element, liquidfied small seafood sources, and letting the bacteria digest the products over the course of 8 or more hours.
It appears very plausible and the user appears to have great success.

I use alot of your PNS Probio and would like to receive your input in how to do this since you know your bacteria.

If I may ask you a few questions:
Does your bacteria digest directly or indirectly the following:
1. Trace elements
2. Amino acids
3. Phytoplankton
4. Liquidfied small organic food source
5. PNS Yellowsno

When the PNS digest these products, one should expect to see an increase population of PNS bacteria right?

Thank you for your input and please offer any additional insight I may have missed!

 

[brandon429]

=have no gut

 

[Kenneth Wingerter]

I would like your expert opinion if I can gutload bacteria such as live PNS Probio?

After reading a thread in the forum, there is a user using bacteria mixed with amino acids with acetic acid carbon source, trace element, liquidfied small seafood sources, and letting the bacteria digest the products over the course of 8 or more hours.
It appears very plausible and the user appears to have great success.

I use alot of your PNS Probio and would like to receive your input in how to do this since you know your bacteria.

If I may ask you a few questions:
Does your bacteria digest directly or indirectly the following:
1. Trace elements
2. Amino acids
3. Phytoplankton
4. Liquidfied small organic food source
5. PNS Yellowsno

When the PNS digest these products, one should expect to see an increase population of PNS bacteria right?

As Brandon pointed out, bacteria are unicellular organisms and do not possess a 'gut' per se. I do see what you may be getting at--that they might mediate the transfer certain nutritional compounds directly from the environment to something else higher on the food chain. To that, I'd say 'generally, probably not?' Not complex compounds, anyway. Trace elements and simpler stuff like that, yeah, probably. I'd have to know more about the concoction you speak of--seems like the 'ingredients' are used to grow the bacteria rather than 'gutload' them.

All that being said, what you feed the bacteria can have a significant impact on their nutritional value. For example, depending on its diet, the protein content of Rhodopseudomonas palustris (the bacterium in PNS ProBio) can range anywhere from 40-some percent all the way up to 70 percent or higher. In another example, carbon availability plus manipulation of photoperiod might generate large amounts of PHB (an energy yielding polymer that make up the biopellets we aquarists are familiar with). In another example, light intensity may be manipulated to increase carotenoid content. And because the species is a so-called phosphate accumulator, it may be rich in phosphorus if grown in a high-phosphate environment. And so on.

1. Yes, R. palustris definitely takes up certain trace elements, some required for its growth and some not. I'd be careful not to overdose mixed trace element supplements however, as exposure to certain elements such as iodine may harm these bacteria.
2. Yes, it takes up any/all aminos as far as I can recall. However, it can synthesize most of the major aminos itself. In one study, its amino acid profile "compared favorably with Food Agricultural Organization (FAO) guidelines."
It does lack the complete set of enzymes and pathways to synthesize all of the major amino acids, such as phenylalanine, valine, isoleucine, leucine and others. The incomplete amino acid synthesis pathways in R. palustris make it auxotrophic (dependent on external sources) for certain amino acids that it cannot easily produce on its own. In other words, it relies on its environment to supply at least some of these essential amino acids. This isn't uncommon in bacteria, as many bacterial species have evolved to thrive in specific ecological niches where certain nutrients, including amino acids, are readily available; I'm supposing that any/all of these would be available in the concoction as you described it.
3. Of course it cannot 'eat' phytoplankton directly, as even a relatively tiny phytoplankter like Nannochloropsis dwarfs the average sized bacterial cell. Indirectly, yes, it can consume (dead) algae and algal exudates generally. This is of particular interest to aquarists for a couple of reasons; firstly, it (unlike the vast majority of other heterotrophs) can degrade the whole algal cell, including its cellulose-based cell wall, and secondly because it can degrade exudates such as the polyphenols that are responsible for a lot of water yellowing.
4. Yes, it can easily degrade the organic matter I'd expect to see in 'liquified small organic food sources.' I'd just be careful to not incubate any foodborne pathogens. Bugs such as Vibrio are well-known to lurk in seafoods, and just recently I believe I've seen coral pathogens such as Arcobacter being found in frozen aquarium food. Eight hours certainly may allow enough time for the bad guys to proliferate. The actual level of risk here of course depends on the source and how the material is handled.
5. PNS YelloSno is really designed to be fed to corals, copepods, tube worms, etc. directly and is (just my guess) best used that way. Particularly because of the trace elements and B vitamins (especially B12) added, this product no doubt can grow R. palustris and many other bacteria (it's used to grow R. palustris, after all). My only concern about leaving this particular product sitting warm for 8+ hours would be spoilage. For this one, I'd actually just add it to the concoction cold, right before feeding time.

Yes, you could expect these bacteria to grow on this combination of ingredients so long as nothing harmed them (competing microbes, antibiotics, toxic substances such as iodine, etc.) and they were incubated at a temperature of 80-85 F. Moderate lighting would certainly help as well.

One last thing worth mentioning is that R. palustris is shown to promote the growth of certain other probiotic species. This may be of interest to anyone who is already using probiotics such as Lactobacillus in these concoctions.

Hope this helps!

 

[reefluvrr]

Thank you for taking time to answer my questions in such detail!

Basically all I am doing is really using amino acid and organic coral food (such as reefroids, Fauna Marin Amin S) to grow more bacteria but likely not enriched with amino acids?

Thus far I only tried the concoction once (PNS Probio, PNS Yellow Sno, Fauna Marin Amin S coral food, Tropic Marin Carbon source, an Tropic Marin Amino Acid) in 300ml of tank water and let it "digest" for 8 hours--

Prior to feeding this concoction, my pH had been between 8.1 to 8.4. After dosing the 300+ml of concoction, my pH dropped down to 8.1 to 8.0 for the next two days. I suspect there was a lot of bacterial respiration which lowered the pH? could it also be some acidic byproduct as well? The reason I say that is my Alk sits at 9.0dkh. I can usually keep my pH relatively high with higher alk. My alk is still high at 9, but pH is now much lower.

I do use a CO2 scrubber for my protein skimmer, but that has not improved pH at all.

I am now waiting to see if the bacterial population will naturally decrease in my display tank over time and pH gradually go back up.

Does this pH drop rationale sound plausible?

Moving forward, I will just stick to dosing PNS Probio directly into my tank without enhancing them with amino or coral food.

Thank you!

 

[Kenneth Wingerter]

Hard to say for sure from here what the pH issue is; could even be the result of some combination of things. You've even got a CO2 scrubber on there, dang haha! But I think you're right, at least in part, for suspecting microbial respiration as the culprit. Even more so if the pH climbed back up a bit a couple of days after the feeding. So yeah, definitely plausible!

Yes, you can put it directly into the tank, but you could also use it as a probiotic food additive (both fish and coral foods). This increases feed conversion (conversion of food into biomass), which reduces waste, which might reduce BOD, which could have some positive impact on your pH (reducing microbial respiration). TBH, that's not an area I've researched extensively, but I've seen a good amount of data out there (studies on fish farms, shrimperies, etc. looking at R. palustris reducing BOD). More googling if you dare hahaha. At the very least, putting it in the food is a plus for the fish and coral health, so a win either way.