Even after I created PermaClone, I struggled maintaining sterile cloners. After all, sterilized PermaClone collars only solve one part of cloner maintenance. You still must master the maintenance of all the other intricacies. It took years to develop the recipes I share for maintaining sterility and achieving consistent results in water culture. I now confidently get consistent result when I clone! My cloners simply don't fail...and produce heavily rooted, amazing clones!
In this article I want to tackle the specifics of water pumps. If you haven't already, be sure to read my articles Hydroponics Water Quality and Treatment--A Must Read and PermaClone™ Manual for Perfect & Predictable Cloning. If you click the links they'll open in their own tabs so you can read them next.
There are two big recommendation I make with regard to hydroponic submersible pumps in cloners and hydroponic systems.
First: Remove the Back Plate
The back plate is an often overlooked portion of the pump. The back plate is found on almost ALL submersible water pumps used in small-scale hydroponics. It is found where the pump cord enters the pump. As illustrated above, it’s a plate which upon removal has an orifice (illustrated below). With most brands it is not well vented for easy access by sterilizers. Meanwhile, nutrient solution can exchange slowly with the small crevices, offering a continuous re-exposure of good OR BAD bacteria. Over time, you invariably get exposed to a bad bacteria; and this orifice becomes infected while sterilizers don’t adequately flush.
There ARE pumps that don’t have this problem. As an example, Elemental® (pictured above), ActiveAQUA™, and EcoPlus® submersible pumps all have ‘gills’ on their back plate, allowing sterilizers speedy access. While EZ-CLONE® and TurboKLONE™ pumps have traditionally not been vented with these gills. I recommend removing the back plate of ALL pumps to avoid unnecessary intricacies in your equipment.
Second: Pump Break-Down
If you have been exposed to a BAD pathogen or experience any decrease in cloning rates, break-down your pump and sterilize the individual components with gentle scrubbing in an oxidizer of your choice. It’s ultimately simple, but daunting at first. If your time is worth more than the cost of a new pump, it may be wise to purchase a new pump. JUST REMEMBER!...remove the back plate and from this point forward follow our techniques for sterilizing your cloner between cycles to avoid the cost in time or money of pump break-down or replacement.
As for the pump, looking at the picture you'll see the impeller assembly. This is shown broken down on the right where you'll find two sample shafts, made of either metal or ceramic materials. The impeller assembly also includes two rubber end-caps, two washer, and the large ring-gasket goes to the Housing Cap. The washers prevent friction between the impeller and rubber end-caps. The end caps hold the Impeller on the shaft and guide the impeller assembly into the pump housing. The rubber end-caps fit into the housing end-cap and a small recess at the back of the motor housing, stabilizing the impeller assembly from the plastic of the motor housing inner walls. The pumps is driven by a magenetic field. You'll feel this magenetic field when your removing or inserting the impeller assembly.
Below are some pictures to help guide you through putting the pump back together.