It’s easy to look at the new Neptune Systems D0S “Fluid Metering System” and lump it in with all of the other dosing devices on the market, but you’d be mistaken. Nearly every facet of the DoS has been completely designed and engineered to be a tool of precise and reliable fluid dosing and metering, which culminates into a tool which is in a completely different league from the typical dosing solutions on the aquarium market today.
The idea of fluid metering is more important than dosing, it means “exactly what you’re putting in and taking out”. The concept of fluid metering is already in use in everyday devices like the Coke Freestyle soda dispenser which uses precise doses of fluid to create exact measurement of ingredients for making sodas. Science and medical applications don’t use the normal “dosing pumps” because it is supposed to be exact, and you can’t get anywhere near precision with a simple brushed DC motor and a tiny tube of silicone.
A peristaltic pump is made up of two parts, the motor and the actual peristaltic pumping mechanism which is turned by the motor. For most aquarium applications which we can agree have all been deemed “non-critical”, manufacturers of dosing pump systems have combined some of the cheapest DC motors and simplest dosing pump heads to keep costs down, while providing a product that sort of does the job. The fundamental problem with combining a brushed DC motor and a narrow diameter pump head is that the “measurement” of fluid, if you can even call it that, is measured in time; as in how long does it take the motor to dispense a given volume.
In our everyday life liquids are never measured in time but in actual volume and there’s a myriad of issues that arise when dosing pumps use time to determine volume dispensed. For starters, brushed DC motors rely on contacts within the motor to transfer current, but over time the contacts wear down and the number of RPMs will decrease with increased usage. Some of the better dosing pump manufacturers have recently adopted stepper motors to get a more precise accounting of RPMs over time but this is only part of the battle to get better and more precise dosing of fluids.
Another source of error in conventional dosing pumps is how the rotations of the motor are transferred to the peristaltic pump head. Many designs simply rely on friction to transfer rotations to the rollers in the peristaltic pump heads. Others may use a system of gears to decrease the RPMs of the motor to the pump head. In both cases problems can arise with this indirect method of turning potential with rollers slipping off the motor spindle and the use of plastic and metal gears eventually resulting in a sheared and stripped gear mess.
The other crucial piece of the physical pumping unit is the actual peristaltic pump head. So many of our aquarium dosing pumps use a very small and very flimsy peristaltic pumping head which use a thin-walled, narrow-diameter tubing that is prone to so much potential for error and failure. The thicker the tubing the more accurate and reliable the dosing of the pump head will be. Dosing pumps are primarily used to dose two-part solutions of supersaturated calcium and carbonates, two solutions which can easily start precipitating inside the tubing causing clogging and sometimes ruptures of the pumping mechanism.
The final physical component of the dosing pump is the external tubing connections. For most dosing pumps a very simple nipple is provided on which the tubing is slipped over. External tubing connections are super important, if they don’t seal well they can suck air or leak but good compression fittings won’t get hard and crack.
It wasn’t our intention to offer a complete overview of how dosing pumps work but it’s important to highlight these points in order to convey how Neptune Systems has addressed every major design flaw in the physical dosing pumps that are part of our aquarium arsenal. On every front Neptune Systems has selected the highest quality components to create the DoS, which can reliably deliver a known volume of fluid from the first rotation to the 1000th.
Stepper motor are used in 3D printing for its exact properties and in this regard Neptune has included one of the highest quality stepper motors available to turn the pump head. Rated for 5000 hours of use, the stepper motor used in the DoS uses a direct transfer of its rotations to the peristaltic pump head, no friction or gears involved. Furthermore, the DoS uses one of the largest available peristaltic pump heads with a large diameter tubing that is suitable for dosing thick liquid foods as well as being less affected by small crystals of precipitated minerals from two part dosing solutions.
Once the physical dosing pump device is perfected, there still lies the problem of how to operate the machine – our standalone dosing pumps are controlled either by basic timers, or with embedded firmware, both of which rely on time to determine the measurement of volume. This is where the DoS truly stands out with incredible software that can be accessed in the cloud through Apex Fusion.
With programmable software it is possible to very accurately meter out fluids and since the DoS uses two very precisely driven dosing pumps with large volume tubing, it is even possible to do automatic water changes, continuous water changes, and all kinds of novel applications of moving liquids from one place to another. There’s still a lot we have to learn about what will be possible using the significantly different DoS fluid metering device from Neptune Systems and we can’t wait until this unique tool is unleashed on the aquarium world. [Neptune Systems]