Hello everyone. It's been awhile since I last posted here. Been in the deciding stages regarding my pond. Basically it comes down to this - I kinda fall between the cracks of a pond / watergarden. The pond I have in mind will be about 40-50 ft. long X 25' wide X 4-5 ft. deep at the deep end, and 2 ft. deep on the shallow end. I'm thinking of tilling in bentonite to seal (instead of a liner). As some of you know, the filtration systems for some water gardens/Koi ponds although effective, can literally cost thousands of dollars. I'm trying to avoid this, and don't really think it will be necessary. However, I do not want a slimy, algae infested mess of a pond on my hands either. I will have a waterfall as part of the overall design, so it will a source of pumped water. The pond will mainly be for asthetics in my backyard landscaping, and to attract wildlife, birds etc. I plan on stocking bluegills, and a few bass. What do you guys think? Any suggestions regarding water clarity and/or filtration requirements of a small pond like this would be greatly appreciated!