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 while producing 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 recommendations I make with regard to hydroponic submersible pumps in cloners and hydroponic systems.
First: Remove the Back Plate
The back plate is often an overlooked part 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 that, upon removal, has an orifice (illustrated below). With most brands, it is not well-vented for easy access by sterilizers. Meanwhile, the nutrient solution can slowly exchange with the small crevices, providing continuous re-exposure to 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.
Some pumps don’t have this problem. For example, Elemental® (pictured above), ActiveAQUA™, and EcoPlus® submersible pumps all have ‘gills’ on their back plates, allowing sterilizers speedy access. In contrast, 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 BreakDown
If you have been exposed to a BAD pathogen or notice a decrease in cloning rates, break down your pump and sterilize the individual components by gently scrubbing them 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 washers, 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 rotating magnetic field. You'll feel this magnetic field when your removing or inserting the impeller assembly.