There are a few different reasons that you could have poor flow.
1. If you have a Variable Speed pump it may be programmed too slow. Increase speed to see if the issue is resolved.
2. Check the pressure gauge on the filter, as low flow is an indication of a dirty filter.
If the pressure is reading high on your pressure gauge, start troubleshooting while performing a backwash. Three minutes on backwash, followed by a 30-second rinse. This will clean dirt and debris out of the sand filter.
Should the pressure remain high try these:
- Check your pressure gauge to ensure it is working properly. When you shut off the pool system does the gauge go down to “0”? If yes, the gauge is fine, if no, replace the filter gauge.
- When was the last time you performed a chemical cleaning on your sand? A chemical cleaning is recommended at least once per season to help rid the sand / glass of oils and gunk that we brought into the swimming pool. Try this method before changing out the sand / glass. If you are still running high after completing this step, you may be due for a sand change. Sand should be changed every 3-5 years, glass every 7 – 10 years. Every filter should be cleaned at least once a season.
3. If the filter pressure continues to run high with reduced water flow to the pool, the pump may be moving more water than the filter is designed to handle. Check the flow ratings of both the pump and filter to ensure they are sized correctly.
4. You may have a blocked or plugged return line. This should cause the pressure gauge to spike.