My goldfish pond

[mrsclem]

Were these sedges planted in some medium or just tucked in rocks? Our last big fish kill- 75% of our koi- was caused because of rotted leaves and plant material that had settled to the holding tank between the bog and pond. Didn't realize how much there was when we restarted pond in spring until the smell of rotted eggs and murky pond water! Your plants were well established but can't believe that that much had built up around the roots.

 

[Tula]

Were these sedges planted in some medium or just tucked in rocks? Our last big fish kill- 75% of our koi- was caused because of rotted leaves and plant material that had settled to the holding tank between the bog and pond. Didn't realize how much there was when we restarted pond in spring until the smell of rotted eggs and murky pond water! Your plants were well established but can't believe that that much had built up around the roots.

I worry about this happening next Spring. I wonder what happens to all the roots over the winter in the bog, then starting it up......trying to think of a way to start it and divert the water out of the bog till it's good and flushed.

 

[mrsclem]

That's why I'm glad I set up cleanout pipes on mine. You could use a shop vac on your supply to your bog to backflush it.

 

[Tula]

That's why I'm glad I set up cleanout pipes on mine. You could use a shop vac on your supply to your bog to backflush it.

This afternoon we opened the two clean out lines and turned the pump on briefly. Boy, a big blob of gunk came spurting out of both lines. We then flushed with a hose. We'll need to plum some type of a by pass before winter.

Our bog still has so much algae and now I know it was also in the plumbing. We are not a text book case of " oh my gosh, the bog took care of everything overnight !" LOL.

 

[Lisak1]

We've never had a problem with dead organic matter in our bog - granted, we keep ours running all winter, but the plants still die back and it's never been an issue. Standing water all winter will be stinky, but I don't think it's dangerous. I've smelled some very "pondy ponds" in the wild that were thriving with plants and fish.

 

[addy1]

I just rake mine in the spring, remove any dead laying on top stuff, turn it on, done!
The water has just a slight pondish smell, nothing bad.

 

[CometKeith]

Were these sedges planted in some medium or just tucked in rocks? Our last big fish kill- 75% of our koi- was caused because of rotted leaves and plant material that had settled to the holding tank between the bog and pond. Didn't realize how much there was when we restarted pond in spring until the smell of rotted eggs and murky pond water! Your plants were well established but can't believe that that much had built up around the roots.

Hi Tula. They were sitting on a large plant shelf in my pond with a couple rocks holding them down but some of the roots went down almost 3 ft in the area where there was no shelf. I did find one small plastic basket that might have been the original when I bought it. That was funny. The sedge would have filled hundreds of those baskets now. The roots seemed pretty clean of debris when I pulled them out but there was probably some buildup of sludge in the middle of the plantings. As soon as I started cutting them it the water got a lot murkier and the fish started flashing and looking poorly again. I couldn’t believe how quickly they were affected so that’s why I thought it was something else. Anyway finally all the fish are active and healthy again. I just lost that one Sanke which I’m sad about but glad the rest are doing well.

 

[AlyssaFish]

Hi Tula. They were sitting on a large plant shelf in my pond with a couple rocks holding them down but some of the roots went down almost 3 ft in the area where there was no shelf. I did find one small plastic basket that might have been the original when I bought it. That was funny. The sedge would have filled hundreds of those baskets now. The roots seemed pretty clean of debris when I pulled them out but there was probably some buildup of sludge in the middle of the plantings. As soon as I started cutting them it the water got a lot murkier and the fish started flashing and looking poorly again. I couldn’t believe how quickly they were affected so that’s why I thought it was something else. Anyway finally all the fish are active and healthy again. I just lost that one Sanke which I’m sad about but glad the rest are doing well.

Sorry if this has already been covered (this is a really long thread!) but I thought I'd mention it anyway. Rotting material can create pockets of toxic gasses that can be very dangerous for fish. That sulphuric smell can be an indicator that there are toxins in the soil/gunk you're working in. If a bunch of it is released all at once, it can pose a serious threat to the fish. I'd recommend draining the pond in the future to drop the water level below the plants you're clearing out. This will keep the water from getting cloudy, prevent anaerobic bacteria from spreading in your pond, and allow you to "de-gas" potentially toxic areas.

Bog plants can be the worst when it comes to the kinds of pockets. There's so little movement in the water that it's easy for the anaerobic bacteria to build up and start making a home for itself. Plants that are placed in soil are often worse for this because clay soils slow down oxygenation in the roots even further, but it's perfectly possible for a healthy plant in rocks and gravel to have the same issues.

 

[CometKeith]

Sorry if this has already been covered (this is a really long thread!) but I thought I'd mention it anyway. Rotting material can create pockets of toxic gasses that can be very dangerous for fish. That sulphuric smell can be an indicator that there are toxins in the soil/gunk you're working in. If a bunch of it is released all at once, it can pose a serious threat to the fish. I'd recommend draining the pond in the future to drop the water level below the plants you're clearing out. This will keep the water from getting cloudy, prevent anaerobic bacteria from spreading in your pond, and allow you to "de-gas" potentially toxic areas.

Bog plants can be the worst when it comes to the kinds of pockets. There's so little movement in the water that it's easy for the anaerobic bacteria to build up and start making a home for itself. Plants that are placed in soil are often worse for this because clay soils slow down oxygenation in the roots even further, but it's perfectly possible for a healthy plant in rocks and gravel to have the same issues.

Thanks Alyssa that sounds like good advice. Yes it is a long thread! Almost 10 years now with an average of almost one per day... but I post a lot more in the summer than the winter. Also my current pond is only 3 years old so the earlier stuff was my smaller pond at our old house. I’m going to build a bog now so feel free to chime in! Thanks. Keith

 

[CometKeith]

Okay so we met with the pond “ professional “ yesterday. I met him on the pond tour and he has done some very large and expensive ponds. I think I could have paid the same price to visit an expensive specialist doctor for what I paid him but anyway I went through with it. He looked at my pump and bio filter and thought that was sufficient. The bio filter is rated for 4000 gallons and I am somewhere 2500-3000 gallons. He liked my idea of building a bog and I was pretty surprised because you hear about the pros not liking them. He calls them “wetlands” because when they build new ponds people don’t like the name “ bog”. So these were his suggestions.. Btw. I have read Addy’s sticky tab on GPF here how to build a bog and also one of the most popular web based article by Nelson Water gardens. Both of those how to do it’s seem pretty similar to me. My pro had some slightly different advice. Im going to install it in the circular area of my pond. It’s where the large planting shelves are and where my old giant sedge was. One of my problems is the shelf is higher than part of the area where I want my blog. The shelf is maybe 14 inches deep and then it goes to 42 inches deep. Originally I was going to drain most the pond and even this off on the bottom and raise it so my bog is only a foot deep or throw down some plastic boxes to level it and put a plastic container on top for the bog. My pro suggested to have two distinct bog areas each with its own pvc pipe bringing it water from the pump. They can be from the same pump but need to be t’d off at some point. Because one pipes is so deep he suggested I use 1.5 inch stone at the bottom of that area but run the pvc at the bottom like I would do at the shallower area. This way my pvc will be at different levels but he said I need a standpipe for clean out for each section. I think he suggested starting with number 6 stone, then number 5 stone and finally the last 12 inches of p gravel. He said it was okay for the pipes to go much deeper than the average 12 inches and long as I used bigger stone above it. So that is one dilemma. It would be so much easier to do this than drain my pond and re-level it. It makes sense to do it his way if that will work. Next he suggested I build a wall of limestone for my bog and bring the new bog liner liner just to the top and cut it. I have a lot of extra limestone so he said to use whatever I have. Im sure I don’t have enough But figured I could buy something. He suggested I drain my water out and put all the fish in a tub to make it easy to work. I’m not sure I really want to do that. I looked up tub and inflatable swimming pools and neither seemed like a great solution and I think it would be too much work to catch the fish. I asked if I could just drain down the pond and drop the stones in for my wall and he said that should work. I found some nice cinderblocks at a job site today and took home about 20 of them so I think I will have enough stone and block for my wall. I’ll put the nicer stone by the top. My pro also said I don’t need to make a waterfall from the bog to the rest of the pond and it’s okay to just let the water mix as long as the water in the bog is higher than my pea gravel. Everything I have read made it sound like the water flows back to the pond from the bog but he said as long as the intake is from the other side of the pond it won’t make a difference about a waterfall from the bog. Incidentally he recommended I move my intake from my filter because it’s too close to the outflow. I was thinking of doing it but he made it sound very important. Also he said he didn’t think the plants were super necessary for cleaning the water in the bog and he has built some without plants. That was pretty surprising! So anyway I’m thinking of starting this project Friday because I’m staying home for the 4th because of covid and this will give me something to do. I welcome any comments and suggestions. Sorry it was soooooo long!

 

[Mayank]

We've never had a problem with dead organic matter in our bog - granted, we keep ours running all winter, but the plants still die back and it's never been an issue. Standing water all winter will be stinky, but I don't think it's dangerous. I've smelled some very "pondy ponds" in the wild that were thriving with plants and fish.

Lisa, what do you mean by you keep yours running all winter? your pump and waterfall? We have a skimmer box and a biofilter falls and we were told that the pump needs to be shut off and removed and placed in garage until spring. Also, we were told to keep the aerator going all winter but to place it on an intermediate level (18 inch deep) as opposed to now where it is on the deepest level (36-40 inches deep) and also to put a floating pond deicer (not sure which part to place it on at this time) to keep a hole open to let toxic gases escape. Now I am confused and worried about spring and beneficial bacteria and filter cleaning and pond cycling etc.

 

[Mayank]

@CometKeith we lost 10 of our 11 big koi. Pulling those big fish out of the pond and disposing of them was so sad. You really do get attached when you watch them grow in your pond. That experience convinced me that I'm a better goldfish keeper than a koi keeper. We still have one big black koi - he's the master of the pond now.

That is so heartbreaking? How did you lose them do you think? I mean you are such an experienced ponder. Now I feel like mine don't even stand a chance and I am getting attached to them. I've gotta be honest, I am freaking out a little bit!

 

[Lisak1]

I think the science behind these "constructed wetlands" continues to grow. I have read a lot recently that the real workhorse in the bog is the gravel. The plants function like they would in the pond by taking up nutrients, but the bacteria that colonizes the gravel is the real secret to using these as biological filtration. Flow rates and volume and surface area are all part of the equation, but I think like much of nature it's more forgiving than mathematically precise.

The plan you have in place reminds me of some of the swim ponds with bogs that I've seen built. The bog is actually integrated into the edge of the pond, much like the edge of a pool is all part of the filtration system. It sounds to me like a winning proposal!

 

[Lisak1]

@Mayank - our pump runs all winter long, waterfall and all. There are factors that make this possible - for example, our pump is six feet below ground, underwater. Our plumbing is all buried - nothing is subject to freezing. And our waterfall is wide and concave, so the ice that forms won't re-direct water out of the pond. We don't have a skimmer box or a bio filter that could crack. So the advice you were given might indeed apply to your pond. Ours has run this way for 8 winters with no trouble.

Well, no trouble EXCEPT last year... we have had issues with our pump plumbing. The pump is in a vault and does not sit on the bottom, so it was creating some downward pressure on the plumbing line where it connects the pump to the main pipe that goes to the bog. It has separated on us twice - once was mid-summer, so no big deal. We just pulled it out and glued it and it was done. We assumed it was just a bad glue job - in fact the old plumber who works in the plumbing department at our local hardware store told us it HAD to be a bad glue job as he had never seen a PVC glue weld fail. So we went with that assumption.

The second time it happened was right before the new year - dead of winter. It didn't let loose completely, but it was leaking around the connection and wasn't pushing the full volume of water. We would have left it alone except we had a string of really nice warm days in early January that year so we decided why not? Well I'll tell you why not - because even when the air is warm, the plumbing and the water are still cold. We disassembled the plumbing, glued it back together and... could not get it hooked up again. We later realized the frost in the ground pushes the main line up just enough that it made the connection impossible.

So due to that completely fluky happenstance, the pump was off from January 10 or so until early March. We ran our aerator, but it just wasn't enough for our big fish. As the pond started to thaw, we could see they were all dead. It was indeed very sad and was avoidable had we only not made the wrong assumption about the plumbing failure the first time around.

When it was warm enough, we hired a professional to come and hook it up and make a few tweaks so it won't happen again.

So that's my sad story. And my recommendation is if you have too many big koi in a pond, your best bet is to keep the water moving. Better recommendation - keep your pond understocked. Or keep goldfish. We had three dozen goldfish when this disaster happened... they were unscathed.

 

[Lisak1]

Oh sorry @CometKeith - long post on your thread!

Back to your regularly scheduled bog!