Koi pond 2010, Okay your two 90 degree elbows equal 16 ft of 3" pipe. I assume that you may use a bulkhead fitting and each of those will add to the length of the pipe. Then all the fittings connecting to the bulkhead will add to the pipe length. Also the fact that water is going from a large area to a pipe and then back to a larger volume adds to the length of the pipe. You could easily get to 30 or 40 ft of 3" pipe. At 30 ft the SC will drop about 2 inches at 2400 gph and at 40 ft it will drop about 2.5 inches. Now looking at the possible air bubble entrapment. Air bubbles are trapped either at elbows or in horizontal runs of pipe that have a high point in the center of the run. The way to fix these problems is the elbows coming out of the filter are replaced with a tee with the through branch of the tee being vertical. The highest end of this tee is left open to the air so that any air inside the pipe can get out. Any elbow that does not turn the water to a downward direction is not problem. The other place you can have a problem with an elbow is where it empties into the pond. If the elbow is on the pond side of the edge of the liner then a small hole can be drilled in the top of the bend of the elbow and the air will bleed off. If water comes out this hole it will flow into the pond. If it is not in this position then it becomes more complicated but can be done. On the tee installation a small piece of pipe may have to be put in the open end to keep the possibility of water coming out. Mike

Vicki, There are many filter systems used by ponders but keep in mind it is a system. Since it is a run off pond with rocks on the bottom I don't think you have a bottom drain. So that in itself means eventually you will have to vaccuum the pond or drain and pump out the mulm and clay that accumulates under the rocks. Most people with rock lined ponds do that yearly. Pond skimmers will help keep the surface debris from eventually ending up in those rocks. Bead filters and pressure filters usually require a prefilter before them, and you must frequently flush them wich requires a lot of water. May not be a bad option if you install a skimmer and use it after the skimmer. But you must commit to those flushes. Your pond is twice the size of mine. How deep is it? What are the dimensions. If it was my pond and the theme was more natural vs crystal clear here is what I might do. I might just use two large skimmers and take them to skippy filters. I don't think I would retrofit a bottom drain due to the clay. So I would do a yearly clean out. If the clay was not that big of a deal I would retrofit a BD to a settling pond or chamber and take that to a skippy. Others with better ideas will chime in soon. Regards, Lisa

Bottom drains are only a bad idea for small fish and tadpoles if your drains are piped directly to a pump. If your drain goes to a settling tank first, then there is no problem because the fish and taddies will be safe sitting in the settling tank until you come along to rescue them. I like sequence pumps....but I do prefer W. Lim pumps. They are more expensive, but they are VERY efficient and well designed and also VERY quiet! I accidently ran one of my Lim pumps for around 20 hours with no water in it and it didn't hurt it a bit!! Here's a link to a DIY filter I built a couple of weeks ago. I am VERY happy with the performance of this filter! Here is a link that might be useful: DIY filter

We have 6 white domestic ducks and one mallard that I rescued from work. I tried putting floating food in the pond, we put feeder comets in the pond that are not even half an inch long.We have a large kennel that is enclosed and over hangs the pond by a foot so they have a safe place to get away from raccoons or anything else that may want to hurt them. We put their food in the kennel they would not go in to eat. We put them in the kennel so the only way out was through the pond, no dice, they stayed there 2 days and couldn't get through the pond fast enough. It was kinda funny to watch but I still would like them to enjoy the pond again. This is frustrating.