If you had a cycling problem you would be seeing traces of ammonia or nitrite in the system, but you dont and your water quality seems almost perfect.
One possiblity is that something in the new water is feeding a bloom of micro-organisms is the water. Silica, phosphate etc, something thats not usually tested for.
What you could try is skipping or reducing the water changes for a couple of weeks. Wont matter is the nitrate goes up to 15 or 20. See if the water clears up. Then do a water change and see if it comes back.
The filter will not be doing anything useful for random cloudyness. The diatoms or algae are too small for the filter to remove. This goes for any common filter media so it wont be a problem specific to your filter.
Possibly smaller more frequent water changes will reduce it?
Can you get an accurate water analysis from the water company? That may give more clue as to what is happening.
Good luck with sorting it out.
Ian
One possiblity is that something in the new water is feeding a bloom of micro-organisms is the water. Silica, phosphate etc, something thats not usually tested for.
What you could try is skipping or reducing the water changes for a couple of weeks. Wont matter is the nitrate goes up to 15 or 20. See if the water clears up. Then do a water change and see if it comes back.
The filter will not be doing anything useful for random cloudyness. The diatoms or algae are too small for the filter to remove. This goes for any common filter media so it wont be a problem specific to your filter.
Possibly smaller more frequent water changes will reduce it?
Can you get an accurate water analysis from the water company? That may give more clue as to what is happening.
Good luck with sorting it out.
Ian