neoprodigy;2421646; said:
it depend on feeding too... there is no standard rule..
No argument Neo, there can be no hard and fast rule. There are simply too many variables including but not limited to;
Temperature
pH
The amount of available carbon for BB (kH)
Dissolved oxygen
Micronutrients (gH)
Plant metabolic activity
Light regime
Biodiversity
Food conversion rates
Waste nitrogen percentage in food
Media surface area and surface area to volume ratio
Flow rates
Turn over ratio
Plumbing arrangement (series or parallel/redundant filtration)
Drip systems
Chemical additions (meds, salts, and fertilizers)
Filtration equipment maintenance schedule
Media permeabilty and porosity
Oxygen levels in the media
Presence of dead spots in the tank
Scavenger activity
Disease or fish mortality, and
Driftwood and dead plant material.
Some readers will see the list above as too detailed and others will recognize significant omissions. Some of these variables change in their relative importance on a daily, weekly, or between maintenance intervention basis. A debate over the details of what degrades our system water is not the intent of this thread however.
Our goal in filtration is to provide a means to remove the mulm and nutrients that result from the metabolic activity and its required inputs of or fish. It is a generaly accepted principle that we compensate for the unknowns and variation in polution rates by providing a Safety Factor.
Some of us remove guess work by using huge quantities of media and design our wet/dry systems accordingly. Others, constrained by cost and space may not be using enough.
Fish such as Oscars and Piranha produce significantly higher waste and would require a larger media volume than would an equal mass of cardinal tetra in a planted tank. Herein lies the challenge.
Monster fish keepers are unique in there experience in this area. It has probably happened time and again where we set up a system for a large tank with a few monster fish and observe over time as the fish grow, not only does the amount of space become inadequate but also the performance of the filtration system degrades. We either increase maintenance (pros and cons), increase the volume of filter media (pros and cons), or increase the flow rate through the media.
What I'm attempting to do is encourage some debate, gather the experiential wisdom of 40,000 fish keepers, and build some consensus on what is a good ratio of media volume to fish mass in a system, recognizing the many variables that make our hobby so interesting and rewarding when the challenge is well met.
