Pond Boss Forums GENERAL QUESTIONS Help What do I do at the bottom of the pond?

So my pond is currently not holding water past what seems like part of the built up dam, it was dug from a ditch that was maybe 4 feet deep and going down hill, had a big sweet gum tree and a dead/dying oak in it. I've drained it a few times (raining off and on, to where they couldn't get machines in there) for the guys that built it to rework the dirt and expand it a little, getting rid of a tree we left on the side, and redoing the dam with a culvert pipe for the spillway to build up the dam flat instead. It was seeming to lose water fast in the beginning, but over a few months it seemed to last longer, still would lose a foot per week of the rain stopping, but then slowing down again once it got maybe 3 feet below the original spillway. I'd say the dam is maybe 6 feet higher than the bottom of the original ditch, but the pond was dug supposedly 6 feet below the original ditch bottom. I'm told the clay looks fine so they are going to try and redo some of it again but do have it in mind to buy some clay.

MY CONCERN FOR THE BOTTOM OF THE POND! I'm hoping it works, but am wondering what I should be doing at the bottom of the pond for the fish, should I be getting sand, pea gravel, or what? In draining many times now it I've had to walk in the mud and it's like 8" my boots sink in, very hard to get out. If I dive in when it fills up, am I going to get stuck down there? Kind of serious. Should I be putting like some landscape fabric before some material on top of it? The pond was supposed to be 1/4 acre and about 10 ft deep, currently smaller than that. But I'm hoping to get some bluegill, catfish, and...I'll have to think of what else works in a 1/4 acre pond. I had 2 red eared sliders find their way to the pond and multiplied to 4, which have since disappeared since draining the pond, hundreds if not thousands of frogs/toads, so there will be stuff for fish to feed off of besides the minnows.

Hmmm....How are you draining the pond? Curious if a trash pump with a dewatering bag might both get rid of some of the "junk" at the bottom of the pond and at the same time allow you to drain the pond. It would come down to where you set the dewatering bag up for discharge on how much of the water, if any, is allowed to reenter the pond.

That "junk" on the bottom would also be pretty fertile if you could get it to a compost bin someplace on site.

It is a trash pump but just out the back of the pond, hadn't heard of a dewatering bag before. The pond isn't that old though, although it does smell like fish due to the thousands of tadpoles that surely died after draining it each time. The suction hose doesn't seem to suck up much of the mud around the end, and the hose isn't very long, I think it'd be quicker shoveling the bottom out than trying to drag the hose and pump motor around as the hoses are barely long enough to reach the bottom and still go out the backside of the pond.

I was not considering having to pump it out in the future, would be an issue if I put pea gravel at the bottom and having to pump it in the future...the thing is I thought fish would want sand/pea gravel to reproduce, I understand that minnows just lay their eggs in grasses and posts, stuff like that.

Edit: While pumping it I basically had the pump motor half way to the bottom of the pond, due to the 15ft hose. I actually called a rental place to see if I could rent a pump hose to add onto it but they said I can't just add hoses as it adds stress to the motor pumping further. I can imagine that being the case when going vertical, but with a 10-12ft deep pond? Still an issue?

Many people make specific spawning areas with pea gravel and sand at the bottom of the pond. I used geotech fabric first, bordered it with block and then put the pea gravel on top at our place. Having some complex habitat close to the area will also give the babies a place to hide after hatching.

Sounds like you are on the right track.

Welcome to Pond Boss!

If you have clay and silt subsoils, then the boot-sucking ooze in the bottom of your pond may be due to eroding material entering your pond after the construction work removed your groundcover vegetation.

If easy, I would remove some of that material with appropriate equipment the next time you drain your pond. You paid good money to initially create your pond depth, don't give it back now!

I would definitely get started immediately on re-establishing your desired vegetation around the pond. If the construction crew left bare clay, you may need to borrow some good topsoil from other areas of your property. If you have to do that, then do it during the optimum conditions for your chosen plants. (For example, do not do dirt work and plant grass at the end of July in Texas. It is too darn hot - do it in the fall. However, you might do some rye grass right now on bare clay if you really have a bad erosion problem.)

I also agree with Boondoggle above. You do not need to cover the entire bottom of the pond with gravel. A few spawning beds (on weed fabric) should be sufficient. Also, some spawning habitat for fathead minnows (read some threads), if that is what you are going to use.

P.S. IMO, the rental guys are wrong and you are right about suction hoses. If you go vertically (at sea level), the theoretical maximum suction height is 34 feet before you start creating a vacuum in your column of "lifted" water. That is totally different from extending your line HORIZONTALLY. Just make sure you use the largest size suction hose that fits on your pump inlet. Theoretically, you could also cause a vacuum and cavitation in your suction hose at maximum pump rate if the "frictional" pressure losses in the hose became high enough. To avoid that problem, just pump out most of your pond with the short suction hose at your maximum pump rate. When you have to add some more suction hose to pump out the very bottom, just operate your pump at lower throttle.

P.P.S. Sometimes Tractor Supply, Harbor Freight, etc. have pump hose "kits" go on sale. I have used those sales to get additional suction pipe, some discharge hose, and some fittings for less than the cost of normal priced suction hose. That is all inexpensive gear, but I don't use my trash pump for any "critical" operations.