| Oyagoi
Join Date: Jul 2005 Posts: 1,003
| Nice John
Let's go through these in a little more depth if you do not mind. Absolutely correct but the "catch" is in the word "can" in the sentanece ending in "that nitrifying bacteria can live on." This often times gets misconstured as to "will" live on. The relationship is actually much deeper. This surface area mus be kept free of debris and detris. It is also dependent on the nutrients (ammonia in this case) suppiled to that surface area. The biofilm reactions are instananeous as its relates to the conversion of ammonia to nitrite PROVIDING that the ammonia molecules come into close enough proximity to the biofilm itself.  |  |  |  Quote: The two primary forms of bacteria that make up the nitrification cycle within biofilters is Nitrosonomas and Nitrobacter. As most of your already know, Nitrosonomas bacteria convert ammonia to nitrite, and the Nitrobacter strains of bacteria convert that nitrite to nitrate. There are other strains of heterotrophic bacteria and enzymes that participate on the over all nitrification cycle as well. |  | |  |
Yep, no problems there. | | | Quote: The bacteria live on the surfaces of what ever type of media is inside the biofilter in what is called the "biofilm layer". The higher the SSA, the more bacteria that can live within the filter, thus the higher the SSA, the more ammonia and waste that can be metabolized. SSA is the base figure used to calculate how much fish waste and ammonia that a biological filter can metabolize in a 24 hour period. SSA is the common denominator across all biological filters and media. It is the "Horsepower & Gas Mileage" rolled into one easy to understand number. | | | |
Now here is where the relationship is often misinterpreted. Above you draw the conclusion that the more surface area available, the more bacteria can live within the filter. This is not necessarily true if that surface area is not maintained and IF the nutrients are not supplied in close enough proximity to that biofilm/surface area. | | | Quote: "All biomedia in fish pond filters or bio filters of any type can be classified according to its specific surface area (SSA). The higher the SSA the more probable is it that the biomedia will be more effective in a fish pond filter. SSA refers to how much surface area per unit volume of a type of media is available for colonization by bacteria inside fish pond filters." Excerpt from www.clean-garden-ponds.com/biomedia.htm | | | |
It is more prbable within that given design but not directly relational from one design to another due to the factors (cleanliness of the filter and rate at which the nutrients are supplied to such). My sources at Evolution Aqua quote a surface area per cubic foot of Kaldness to be as follows: 1 cubic feet of Kaldness = 274 sq ft of surface area I am not sure of your other SSAs' are correct or not | | | Quote: It is impossible to know how many fish a biological filter can support, and how much fish waste and ammonia the biological filter can metabolize without knowing its SSA. SSA tells you how much nitrifying bacteria can live on the media - the biofilm layer as it is commonly refered. You don't know how much gasoline your car burns without knowing the Miles Per Gallon (MPG) - well, SSA is the same type of critical number to know. | | | |
Even knowing these factors you cannot adequately determine how much fish/waste a filter will metobolize iunless you can also determine the ongoing cleanliness of the media, the flow rate and it ability to pass the nutrients in close enough proximity to the biofilm itself. | | | Quote:
It is commonly known, and widely published in study after study that it takes an average of 10 square feet of biofilm (SSA) to metabolize 1 gram of phyiscal fish waste per 24 hours. It takes and average of 50 square feet of biofilm (SSA) to metabolize 1 gram of ammonia per 24 hours. Fish, including koi, produce an average of 33% of their total body weight in waste per 24 hours. Fish, including koi, excrete .1 grams of ammonia per 1,000 grams of body weight per 24 hours. These statistics are compiled from State Fisheries, University Aquaculter Studies, Hatcheries, Breaders, and Human Food Fish Farmers.
| | | | Again, I'd like to see those studies since again, wiothout knowing the other factors the measurement quoted is a "guess" at best. SSA Does NOT tell you exactly how much biofilm a biofilter contains. Again, there are other influencing factors. Once again, that is within a perfect filter, one maintained clean, free of all debris, all of the time, and passing all nutrients within the prescribed proximity range. Its a starting point for a perfect world, again not a hard measurement that is true in any/all situations. | | | Quote:
SSA tells you how much fish your biofilter can effectively support.
Thanks so much for the question.
Sincerely,
John Russell
President/CEO Russell Watergardens
| | | | Once again, its a starting place and an estimation at best. When this number is misconstrued, it can lead to disaster. Let me4 give a couple of examples from your website: http://www.russellwatergardens.com/pondstyle.htm | | | Quote: Since the traditional koi pond doesn't' have the added surface area that gravel, rocks, and plants provide - the filtration systems are usually larger - with much higher volumes of surface area for bio-film colonization. They are designed to remove waste as it falls to the bottom of the pond through bottom drains instead of relying on bacteria colonization at the pond bottom to break down the waste. They usually have a UV in the system to help keep the water clear of free floating algae that would turn the water green because of their lack of plants that aid in starving out algae. | | | | Now John, we both know that gravel in the bottoms of ponds collect waste. Anyone who has ever had to clean one realizes how detroimental this can be to ANY koi, not just those that you say wish to be kept at optimum health. This waste is not totally broken down and in fact collect at what I personally would consider a high rate over a rather short time span. Now you talk in the paragraph above about added surface area due to the rocks themselves for added biofilm. Since this surface area (rocks) is not maintain in a clean condition and there is virtually no water movement overthem, the little added surface area is actually negated as compared to that of a smooth sided koi pond is typically less.
As for Koi pjnd filtration, most advanced hobbyists learn the value of highly oxygenated bio-chambers. Most are under the misunderstanding that the aoration is provide for O2 within the chamber. This is in actuality a negligable effect. The real positive effects are a) it keeps the surface area clean by reducing/eliminating the ditrus build up on the media thus allowing the biofilm a clean surface and keeps that biofilm from becoming strangled so to speak by these solids. It aslo, b) increases the currents within the chambers creating multiple passes of the water column through and around the media increasing the likelihood that the nutrients will pass within close enough proximity to the biofilm.
So although you explaination of SSA is factual, your application of such, particularly on your website is misconstrued.
As for the "raking" of the rocks? Well, that is a practice that I wouldn't recommend since it releases waste and gases back intot he water column that could very well be detrimental if not lethal to the koi. Also remember one simple principle. Whether rasing a koi that is a family pet, or raising a grand champion, the environments for a helthy koi remain the same.
Steve Childers |