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.)
