why dose PRODIBIO BIODIGEST.

[bushdoc]

There is no scientific evidence that adding bottled bacteria to established tank is of any benefits. It might be useful to cycle tank initially.
Best source of bacteria in post cycled tank is fish poop, live rock, coral frags, snails, crabs and other live critters you buy from LFS or online vendor.

 

[mcgullen]

My recent tests show that BioDigest has no clear effect over carbon dosing on ammonia, phosphate or nitrate. I have tried freshwater and saltwater using both freshly made water and changed out tank water. I have tried multiple carbon sources. Nothing can make Prodibio BioDigest show any clear difference over just carbon dosing.

I do have 16s rDNA test results on BioDigest and can see that the vial does contain bacteria. It’s just that the bacteria don’t appear to be doing anything.

Prodibio BioDigest Likely Has No Effect On Ammonia Oxidation and Does Not Help with Waste Reduction

No positive results whatsoever. I have repeated all model tank tests with same results. I have used BioDigest as instructed on established aquariums and monitored their TAN, PO4 and NO3 levels, only to see no difference as compared to controls for 2 weeks. Is there anyone who knows what...

www.reef2reef.com

 

[Dan_P]

My recent tests show that BioDigest has no clear effect over carbon dosing on ammonia, phosphate or nitrate. I have tried freshwater and saltwater using both freshly made water and changed out tank water. I have tried multiple carbon sources. Nothing can make Prodibio BioDigest show any clear difference over just carbon dosing.

I do have 16s rDNA test results on BioDigest and can see that the vial does contain bacteria. It’s just that the bacteria don’t appear to be doing anything.

Prodibio BioDigest Likely Has No Effect On Ammonia Oxidation and Does Not Help with Waste Reduction

No positive results whatsoever. I have repeated all model tank tests with same results. I have used BioDigest as instructed on established aquariums and monitored their TAN, PO4 and NO3 levels, only to see no difference as compared to controls for 2 weeks. Is there anyone who knows what...

www.reef2reef.com

Is there a chance that the sample you tested was dead?

@taricha has done studies on bottled bacteria and it was only after he provided a banquet-like medium (by my standards anyway) did they show activity. It struck me that if the bacteria require this sort of food, they might show pathetic performance in an aquarium.

 

[taricha]

1. why do you dose it, if the tank looks fantasic?
2. is it just good maintenance?
3. What is BAD bacteria?
4. where does it come from?
5. what are the signs that i would need to combat BAD bacteria OR Have Bad bacteria?
6. Do i just assume i have BAD bacteria. and start dumping it in? rule of thumb in this hobby is "DO NOT DOSE UNLESS YOU TEST" can you test to determine the need for adding BACTERIA supplments.
7. BI weekly dosing tells me that the fight against Bad bacteria is a losing battle. thus the requirement for bi weekly dosing. is this correct? refer back to question 4.
8. what are signs that its working or has worked for you?

I'm going to give my answer to these questions as though you asked about Carbon Dosing instead of this bacterial product.

That is, following Randy's line of logic here....

I would in some ways equate constantly adding bacteria such as Biodigest with organic carbon dosing.

1. to feed organisms and lower measurable amounts of NO3, PO4.
2. yes, if done in a consistent way - see 1.
3. outside of the detectable known pathogens - a small but growing number, bacteria have roles and their presence indicates their role is required. It would be hard to argue that any part of the community that isn't a pathogen is a "bad bacteria."
4. pathogens exist in water, live rock, corals themselves, food etc.
5. short of a bacterial genetic test, or presence of coral tissue loss, brown jelly etc - none really. even the genetic testing has an easier time detecting some pathogens and a hard time with others. There's no reason to think a carbon dose could be demonstrated to choke out bacterial pathogens, so that's not a very good reason to carbon dose.
6. I have tracked the processing of modest sizes of organic carbon doses (by O2 consumption) - a modest sized carbon dose is essentially gone by the next day. So a daily dose is logical, but it doesn't have to be every day.
7. I repeat carbon dose for the reasons in 1, not any belief they protect against pathogens.
8. I can see the volume of colorless bacterial film and skimmate change in response to a carbon dose. I can also measure nutrient differences. I can see the film on glass be colorless with a carbon dose vs green/brown without. At high carbon doses, I can watch cyano patches in my sump recede, and then regrow when the carbon dose is stopped.

All that is to say that there is a very clear evidence-based case for a carbon dose being useful - and a number of bacterial product makers know this and ensure that their product acts a lot like a carbon dose, even if they can't always (ever?) be sure their bacteria activate and do stuff in our systems.

(If this sounds like a blanket encouragement of the use of bottled bacterial products - I would say that I know exactly the nutrient sources and amounts when I carbon dose, but not if I use a bacterial product.)

 

[mcgullen]

Is there a chance that the sample you tested was dead?

@taricha has done studies on bottled bacteria and it was only after he provided a banquet-like medium (by my standards anyway) did they show activity. It struck me that if the bacteria require this sort of food, they might show pathetic performance in an aquarium.

Hi! It is not likely to be dead strains. The BioDigest sample from the same box was good enough for PCR amplification as part of my 16S rDNA sequencing test on the product.

 

[Randy Holmes-Farley]

Hi! It is not likely to be dead strains. The BioDigest sample from the same box was good enough for PCR amplification as part of my 16S rDNA sequencing test on the product.

Wouldn't that detect dead bacteria the same as live ones?

 

[taricha]

Wouldn't that detect dead bacteria the same as live ones?

Yes, within a narrow window.
I think aquabiomics has said that DNA degrades pretty fast (like days or ~a week) - before the application of the fixative for preserving - so when you detect those sequences in your system, it's something that is alive sometime in the past few days.
If however, the bacterial product comes with a preservative - then maybe it is possible the cells were dead but still contained preserved genetic material.

looks like pseudomonas is not a spore-former so a preservative in the bottle doesn't seem a good option for delivering live bacteria of this type.

 

[Dan_P]

Yes, within a narrow window.
I think aquabiomics has said that DNA degrades pretty fast (like days or ~a week) - before the application of the fixative for preserving - so when you detect those sequences in your system, it's something that is alive sometime in the past few days.
If however, the bacterial product comes with a preservative - then maybe it is possible the cells were dead but still contained preserved genetic material.

looks like pseudomonas is not a spore-former so a preservative in the bottle doesn't seem a good option for delivering live bacteria of this type.

Is it possible that the medium maintains the bacteria in a stationary state for awhile before they start to die (for the non-spore formers)?

 

[taricha]

Is it possible that the medium maintains the bacteria in a stationary state for awhile before they start to die (for the non-spore formers)?

For the nitrifiers, simply a blank medium with little nutrients and strains that handle starvation well seems to be a good combination.
There tend to be plenty alive still when the user adds them to the system.

I don't know what the approach to keep heterotroph non-spore formers like pseudomonas viable in a sample for a long time would be.
Perhaps it's the same as nitrifiers - just give them a blank medium and let them handle starvation as well as they can.