A debris catching device for surge tanks in swimming pool circulation systems prevents debris from building up within a surge tank. The debris catching device includes a net member for capturing the debris before it enters the surge tank and an elongate main body that is adjustably extendable to select lengths for proper installation. A drawstring cord extending through the length of the elongate main body and around the lining of the net member is provided for cinching the net member closed around the exterior of the gutter drain pipe so that the captured debris doesn't spill out of the net and into the surge tank. A support cord attached to the elongate main body and having opposite ends attached to the lining of the net member may be used for holding the net member in an upright position.