Sizing aquaponic pumps is vital to the success of any in-home aquarium/aquaponics filter. The video offers a minimum rule of pump capacity to supply a grow bed as once the capacity of the aquarium every two hours. I prefer to use the guide of the capacity of the fish tank once an hour. Either way the once every two hours is stated as the bare minimum anyway. Often the actual amount required is determined over time and observation, but it is best to ensure the pump can handle the system when it is mature.
Sizing aquaponic pumps also must take into account he resistance gravity always places on pushing water up. In almost every aquaponic system, the water must be moved up from the fish tank to the grow bed. The vertical lift required is termed head height and can reduce the actual output of the pump dramatically depending on the design of the pump and the distance the water must be lifted.
Most pump manufacturers rate the output of a pump at a level exhaust with no head included. This is often useless in determining the right pump. Often, though the packaging will include a chart that identifies the outputs over a range of head heights. This is place to determine if the pump you are considering is the right one.
Sizing Aquaponic Pumps must consider Head Height
The design of the pump often determines how much gravity will decrease the actual flow rate at a given head. Some pumps are made with leaky seals and were never meant to be used to push water up. Many Power Heads are in this category and rarely have any identification of values for head heights. Pond pumps, as well as statuary pumps are often better candidates when sizing aquaponic pumps because they have been designed to supply water ornaments and waterfalls at various heights.