Frequently Asked Questions

What material should I use?

That depends on temperature, particle size, and chemistry. Most of the filter bags we sell are made from polypropylene felt (PO), so start there. For higher temperatures most people go with polyester felt (PE). For more demanding applications we usually end up recommending absolute rated nylon mesh (NMO).

Why aren't my bags lasting as long as they used to?

Usually because they are working harder. Bag life is limited by the amount of dirt captured, not by hours in service or gallons processed. Bag filtering clean water may last a year. A bag filtering mud may only last a few minutes. A product can appear clean to the naked eye and still be full of particles that are too small to see.

How do I know when to change bags?

Monitor the inlet pressure. The pressure drop across a bag rises as the active surface area is used up. When the pressure starts to raise faster the bag is almost used up and should be changed. Every application is different, but a good rule of thumb is to change bags when you see 8-12 PSI pressure drop (the difference in pressure between the filter's inlet and outlet).

How many times can I clean and reuse a filter bag?

Filter bags are designed for one time use. Attempting to clean a bag will stretch the material. Some holes will get bigger and allow dirt to get through. Other holes will get smaller, plug up faster, and start removing things from the product that are supposed to stay in it.

What does the 'P' in the middle of your part number mean?

In example part PENG10P2S (first P is material PE=Polyester Felt) second 'P' stands for plain (no cover over the entire filter bag). Until the advent of modern glazed felt it was common for filter bags to have an outer cover. You can still special order PENF10M2S bags which have a muslin cloth cover. 

Why are there bubbles in my aquarium when I replace filter bags?

You are using polypropylene felt PONG bags that are glazed and have small traces of foreign chemical; this chemical is NOT harmful to the aquarium life. These bubbles can be reduced by pre-washing your filter bag in clear fresh water (three rinses should do it).

Do you offer volume/distributor discounts?

We do offer volume discounts, but that is based on the quantities ordered and frequency of orders. Contact us in regards to volume discounts and we will gladly give you more details.