I have a small pond and put fish in it yesterday. I put a 1/2" screen of hardware cloth and the entrance of the outlet pipe to keep the fish in. But I'm concerned that vegetation will quickly clog it up and cause the pond to overflow.

How should I deal with this problem? I've been reading on this site about a siphon. I'm not yet sure how that is constructed. But is it OK to just use a screened outlet pipe?

We probably don't know enough about your situation to give you a definitive answer, (size of pipe, amount of water flow, etc.), but generally speaking using a screen or other device to keep fish in can cause a great deal of distruction if it becomes clogged.

The pond is about 50 feet in diameter with an 8" outlet pipe. There are a couple of springs feeding the pond and some creek water which I can turn on when I need it. I'm not sure about the gallons per minute (without the creek water). I'd have to measure it. Just a guess: maybe 2 gallons per minute. Maybe 50 gallons per minute with the creek water. The pond is perhaps 5-6 feet deep in the middle.

I noticed some algae build up on the screen yesterday. I'm not at the site, but will be back there tomorrow.

There was another similar recent thread about something similar in the last couple of days.

I fully agree with my good friend Bing. We don't know enough about your situation.

Like, how big is your pond? How big is the drain? How big is your emergency spillway?

In general, you shouldn't lose many fish, if any. I don't have any proof, but I strongly feel that very few fish ever go out of drains or spillways on ponds less than several acres, unless you have a major dam breach. If you had a pond that was more than 20-40 acres, with several feet of water in the emergency spillway, I might be concerned.

I'd be far more concerned about clogging the water outlets and causing a disastrous situation that would result in a loss of the fish and the pond.

Ken

I'm in a similar situation and want to build a fish exclusion cage to place at the siphon inlet to keep the fish on the outside.

This past weekend I manually started our siphon in anticipation of the weekend rain event and when I shut it off yesterday, there were several 5" BG in the "pond" around the outflow pipe. No telling how many made it downstream in the 28 hours or so the siphon was running.

I'd like to build a 3' cube to place at the siphon inlet and put the pipe inlet inside the cage.

I searched but couldn't find what I was looking for. If anyone can direct me to a thread on the subject I would appreciate it.

Thanks,

-RFL

I've used "catch basins" very successfully for filtering debris while bringing water in from streams to ponds, and I've used them very successfully to keep fish from going out of draw-down lines in ponds that we seine. They are available from about 4-inch to 12 inch pipe sizes. One side can be capped off.



They are really meant for places like driveways and yards, where the top is at ground level. If put at water level in a pond they will clog with debris. But, if they are sunk to the level you wish to draw down to, they will collect very little debris, and they aren't going to let a very big fish out of the pond.

If you are using 4 or 6 inch siphon hose/pipe, an "atrium grate" also works well, as long it is not at the top of the water -- although I have an 8-inch grate like this on the top of my main pond's stand pipe. They are less than $10 at places like Home Depot, Lowes, Menards, etc.


Lastly, if you are using pipe/hose 4-inches or smaller, you can use trash pump strainers. They are available, usually for about $10, with multiple kinds of threads for standard NPT pipe fittings.

I would take the advice of the folks here on this topic....I'd rather risk losing some fish through the drain rather than ALL of them because the overflow clogged. Water WILL find a way out, and it doesn't take long at all for flowing water to eat through dirt.