For the first month of the season I had no problems with my Eco Kleer multiport filter. Then, last weekend, it started leaking a significant amount of water from the base of the multiport and the water tank, enough to visibly drop the water level before it was noticed. The pump and filter are still pushing enough water to recirculate. I tightened the connection (no help), removed the multiport and reset the o-ring and retightened. No help. Could this be an o-ring failure? What would cause water from the water tank to start leaking significantly overnight? Thanks!