IN REFERENCE TO PVC COVER-I HAVE 2.5 TO 3 ACRE POND IN EAST TX. TWO PRETTY WIDE CHANNELS APPRX. 25 TO 30 FT. WIDE COME INTO THE MAIN POND WITH PRETTY HEAVY BRUSH OVER HANGING THE BANKS-BUT NOT THE MAIN POND-THE CHANNELS ARE 4'TO 5'DEEP EXCEPT AT THE SHALLOW ENTRY POINTS - THESE CHANNELS FORM A POINT IN THE POND MAKING THE POND AN-M-SHAPE WITH THE TOP OF THE -M- BEING THE MAIN PART OF THE POND-THE DEEPEST PART IS 7.5 TO 8 FT.I HAVE SCRAP 6" PVC PIPE CUT 24" LGTH. RIVETED TOGETHER- 3 ACROSS THE BOTTOM THEN 2 THEN 1 TO FORM A PYRAMID APPROX. 18 TO 24 INCHES TALL-THEN DRILLED 1\2 HOLES WILDLY ALL UP AND DOWN AND IN DIFF.DIRECTIONS IN ALL THE PCS. OF THE PVC PIPES AND STUCK 1/2" PVC PIPE CUT TO DIFF. LENGHTS IN ALL THE HOLES OF THE PYRAMID THEN BOLTED 6"X6" HAYDITE BLOCKS TO ALL FOUR CORNERS OF THE BOTTOM FOR WT. AND TO KEEP IT OF THE BOTTOM -ANY IDEAS AS HOW AND WHERE TO SINK THEM -ALSO WOULD THE SHALLOW ENDS FO THE CHANNELS BE A GOOD SPOT TO PLACE ROCK & HEAVY BRUSH (CEDAR TREES) FOR PRAY FISH COVER & ADDING CRAYFISH- THESE AREAS ARE PRETTY SHADED - I HAVE GRASS CARP SO THERE IS LITTLE COVER EXCEPT FOR THE OVERHANGING BRUSH-IN THE CHANNELS--THANKS FOR ANY SUGGESTIONS....HARVEY