The elements can be adjusted by either turning them more revolutions or less. If the elements are screwed on too tight, the screen within the post filter can become damaged. This will not negatively affect the performance of the element. The only purpose for the screen is to keep the media within the element during shipment. Secondly, a “lock” condition can occur, where upon the water coming through the element and post filter will stop flowing into the bottom chamber once the water level reaches the bottom of the post filter. To solve the lock condition, the post filter needs to be loosened slightly so that enough water can escape to prevent pressure from building up within the post filter element(s). In other words a small amount of “burping” (spill) is necessary for the elements to perform properly.
To obtain optimum flow without a lock condition and to not have excessive water seepage, you can adjust the post filters a bit each way, to reach a proper balance. Again, the number of turns is a guide. If it appears that too much water is seeping between the threads, the post filter can be tightened a bit more, using care to not overt-tighten. If the system air locks, then the element(s) should be unscrewed a bit.