Water Filters
ABOUT DISK Filters AND SDF Products
Rain-Tal filters are made with patented unique plastic “Super Disks” and are sold under the trade name “Super Disk Filter”, the trade mark SDF™ with the logo:
Each disk is formed with a continuous raised sinuous rib extending radially on one side and annular ribs extending circularly on the other side. When the disks are stacked together small filtering passageways are formed in-between. This structure with the flow streamlines are illustrated on the right/below.

As seen, the dirt is accumulated in the exterior of the sinuous rib, where its smooth area enables easy cleaning by back flush. Other disks are made with multiple radial grooves as seen in the lower illustration and the dirt is trapped inside the grooves. Removal of the dirt from the grooves is difficult and requires opening of gaps for flushing.
The SDF Rotary Regenerative filters can be cleaned and regenerated without opening gaps between disks or removing it out of the filter.
Our water filters are made in few diameters for a variety of applications using disks of selected color coded mesh: Fine mesh of 5 microns for fresh water systems, medium mesh for irrigation and lower mesh grade for sewage recycling.
Our Stacks of Super Disks are sold as custom designed Disk Elements that fits into metal canisters or existing OEM plastic Dismantled Filters. Similar stacks are the Open Filters that are used for river pumping, for gravity irrigation drip systems and for sewage recycling. Some come with a skeleton that tightens the disks stack.