Trying to decide between a floating vertical shaft pond stirrer or shore mounted pond stirrer? We’d 100% recommend shore mounted every time – and we’ve got the science to show you why…
When investing in a stirrer you want something that’s going to get the job done as efficiently and effectively as possible…obviously, otherwise what’s the point? So the first thing to keep in mind is what you want to achieve from stirring:
The aim of stirring your effluent is to keep solids in suspension ready for pumping out.
Why?
Because there are several unwanted issues that occur if you allow solids to settle:
- Accumulation of solids can lead to blockages in your pump and/or irrigators.
- Nutrients lose value when solids are left to settle in the pond.
- Effluent storage capacity is reduced which can impact on council compliance.
- You end up creating an additional job in cleaning out the pond with a slurry tanker or getting a contractor in to dig it out.
This leads to why we recommend shore mounted or PTO pond stirrers over floating vertical shaft stirrers…because they are far more effective in keeping those solids in suspension for the entire effluent pond. Here’s why…
To create a stirring action that will get the entire pond swirling, you need to create a strong horizontal flow of water with sufficient velocity to carry the suspended solids. A consistent speed of approximately 0.8 metres per second will stop solid particles from dropping out of suspension, and the only way to do this is by creating a strong horizontal thrust. This is where a shore mounted electric stirrer is recommended as they are able to provide the right combination of angle, power and speed to churn up the entire pond.
In the past, floating vertical stirrers were promoted for having low power requirements, however these are not recommended for the following reasons:
- Having a vertical shaft the solids are merely pushed away from the propeller, and will then slow down and drop out of suspension in the water, so they never end up being effectively mixed. Moving the stirrer around the pond will only shift the solids from one area to another, so nutrients are not getting mixed in and therefore don’t end up leaving the pond.
- While some floating effluent stirrers may have low power requirements, a lot of the time these need to be run constantly to achieve any results.
- In terms of safety it is always better to keep electricity out of water, and not have the need for anyone to venture out onto an effluent pond should the stirrer require maintenance.
Another option which has been suggested in the past is using a pump type stirrer. In theory these stirrers should work, however in reality you would need a massive pump, or even several pumps to even come close to what a shore mounted stirrer can achieve. In fact, independent studies have proven Nevada electric stirrers with a Typhoon™ Propellor, to be 10x more efficient than a pump type stirrer.