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Old 05-25-2011, 08:58 PM
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+1 I was going to say the same thing but you beat me to it.... mmmhmm

Quote:
Originally Posted by Wanderer View Post
Bio pellets are a viable method of nutrient control / elimination. The largest oversight most people have with this approach is proper … fertilization for lack of a better word. All animals require Nitrogen, phosphorus and potassium (NPK) in given ratios aka the Redfield ratio. potassium in a reef system is frequently overlooked as it generally is in low demand in your average system. When you look at a pro biotic system (zeovit, pellets, vsv or whatever) where you are culturing bacteria in large quantities typically potassium will run out. so that would be point number 1.

other nutrients can be in improper ratios as well too much phosphate for example will usually persist in most tanks as it is much higher in concentration in wastes than nitrate is. so in such a case, running gfo would be necessary or perhaps it might be interesting to DOSE KNO3. I'm not advocating this, simply stating that in principle it would work.


The issue of pellets clumping versus aggressive tumbling is an interesting one. I actually did a fair bit of research in university regarding the productivity and health of streams based on water velocity, substrate size and shape. This is essentially the same principle. what research has found is that in streams where the gravel beds have rounded or slightly rounded particles regardless of size, the water can actively tumble the substrate and the flow through of water is not restricted. This allows for optimal generation of micro flora and fauna which forms the basis of the trophic web.

In slow moving / borderline stagnant bodies of water the production is limited by lower levels of nutrients and oxygen or CO2 being delivered to colonies of micro fauna / flora. These areas actually aid in proliferating larger organisms which feed on the animals / plants produced in the more excited bodies of water. Additionally the slower waters tend to accumulate more detritus and nutrients via decomposition and therefore can lead to larger colonies of plants and decomposers.

Aggressively flowing water with high levels of agitation between substrate particles slough off colonies of micro organisms, sometimes prematurely. this is not necessarily beneficial to productivity. and usually results in high turbidity and low productivity in a river or stream.

so what does all this ecological mumbo jumbo mean for the reef keeper using bio pellets?

that the differentiation between given microhabitats is the key. a good flow - through of water to provide oxygen and nutrients with lower flow areas for the maturation or microorganisms and biofilms that will be sloughed off in higher flow areas. bacteria proliferate more effectively in slightly thicker bioflms, so encouraging there development to a point is beneficial. This translates to a PROPER reactor that moves the pellets around enough to prevent clumping but not so much as to retard the development of biofilms.

Its all about finding that sweet spot of flow through (proper reactor, flow rate) and nourishing the bacteria properly. Keeping your KH at the Proper levels is also necessary.

Dosing a bacterial supplement also insures the correct species of bacteria is at work on the pellets. While other methods may promote a myriad of bacterial species feeding on various carbon sources the biopellet method relies on a few bacteria species. Most of these bacteria will be removed via your skimmer when the methods are used properly. Dosing multiple carbon sources seems more complicated than it has to be. if you were to culture these many species of bacteria for feeding purposes for filter feeders, then it makes sense. For crude nutrient export, giving a limited number of bacterial species the advantage over many makes more sense, and greatly simplifies the delivery of carbon for the bacteria to consume. not to mention the benefit of having the carbon in an inert pellet confined in a reactor instead of freely available to anything within the water column.

just my two cents, as i have noticed the benefit of bio pellets myself and for once, my supremely nerdy tendencies came in useful.
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