Planning stage!

[Lesley Gilks]

Hi...I'm new to the Forum. I'm hoping there will be lots of great advice before I start my project in August. I've always kept aquarium fish but I've always dreamed of having a large garden pond. We recently moved in to a house with a garden that will accommodate my ambitions. We've inherited an existing pond. However, it has some fundamental flaws that need putting right. It had some fish and lots of weed with several plants close by that continually dropped leaves and flowers in the water. This caused a lot of sediment and poor water quality. During the Spring, I tried to rock out the pond but found that the sides were very steep and it was barely 20 " deep. It also had a tarpaulin on top of the liner so I guess that at some stage, it was leaking and it was an attempt to rectify this. Size wise, it's not too bad (12 ft x 9 ft), but I'd like to keep Koi so it's going to be re-dug soon. I'm aiming for 15 ft (L) x 12 ft (W) x 3 ft (D) which will give me a water capacity of 3400 gallons (Approx). I want a natural pond so was initially thinking of going down the root of a skimmer and Bio falls filter but since I've been watching too many YouTube videos, I now love the thought of a negative edge waterfall and stream into a bog filtration system. This is more practical than you may think as the pond is accessed from all sides so this will give me a great view from the other side of the pond. There is also a slope on the far side so rather that having to build it up, it would be working with gravity and the terrain. I calculate that I'll need a 9 ft x 6 ft bog filter to give me the 30% of the overall size of the pond. I'm thinking of using the Aquascape Centipede and Aquablocks for this. Does anyone have experience with this product? It is expensive but I'm looking for easy maintenance with a natural look. The photos are of the pond in it's current condition. I can't go beyond the paving stones as there is a drainage pipe running underneath so everything is going to be focused on the other side. Any suggestions will be gratefully received. Many thanks in advance.

 

[Lisak1]

Welcome @Lesley Gilks to the GPF!

We built our up flow bog using an Aquascape centipede and Aquablox and we have a negative edge that drops into a 1000 gallon rain exchange which also has a centipede and Aquablox. What specific questions do you have?

And yes - the equipment was not cheap, but it's well built, easy to work with and will last forever once it's installed.

 

[Lesley Gilks]

Thanks for the reply. It's good to hear from someone who has the same sort of set up that I'm aiming for. My main questions are; How many Aquablocks will I need for a bog filter of 9 ft x 6 ft size. Looking on line, it looks as if it needs to be about 4 ft deep. What type of aggregate did you use? I've found a supplier that has oyster shells...the claim is that it stabilizes the PH levels so could I incorporate that into the filter media? The centipedes come in 6 ft lengths so one should be sufficient, I think. The basin for the negative edge pool will also need blocks but does this need to be of a specific size? What size of pump am I going to need for a 3500 gallon pond? Can't think of anything else at the moment. X I love the pond, BTW!

 

[Lisak1]

Bog depth is an interesting question - some people build them 18 inches deep; mine is 4 feet deep. Others are anywhere in between. We built ours deep to accommodate the centipede and snorkel. People will tell you that too deep is going to be a clean out issue. In 8 years we have never had a need to clean out the bog. I've dug down two feet and the gravel is clean and not one bit smelly.

Our bog has a layer of softball sized boulders around the centipede. On top of that we have a layer of Aquablox. (I honestly don't remember how many... maybe four? Six?) On top of that we have another layer of the softball sized rocks, then a layer of river rock (about golf ball sized) then we finished with a layer of gravel. We did not use the tiniest pea gravel; ours is a bit bigger, maybe the size of a raisin? (Trying to use common sized items here to illustrate size!) I've never used oyster shells, but I know some people do for the reason you mentioned.

Your goal should be to turn over your pond 1.5 to 2 times per hour. I'm not a pump pro but I do know that how high you need to pump the water comes into play with sizing the pump. Maybe someone else will chime in here with some advice on that.

As for your basin, that's another math equation. You need to consider what will happen if you turn off the pump (or the power goes out) - will the pond continue to empty into the basin and for how long? You want the basin big enough to hold that amount of water AT LEAST. Ours, like I said, holds 1000 gallons. When we get rain, it gets filled up. When we lose water due to evaporation, the water level in the rain exchange goes down, not the pond. We built it big so we could always hold more than we need. We have our sump pump plumbed into the rain exchange to capture that water as well. Occasionally there is too much water due to heavy rain, but we have an overflow that will slowly reduce the level.

Hope that helps!

 

[j.w]

Will be fun watching you do the new build. I don't have a bog and just goldfish in my pond. Love your setters. We had an Irish Setter many years ago. He was called Sir Hector of Shire on his papers, we just called him Hector and he was a big silly clown to say the least.

Very old photos:

 

[Lesley Gilks]

They are beautiful family dogs. We have a 12 week old puppy called Nelson, a 4 year old called Leo and an 8 year old called Rigsby. We lost our old boy Benson just before Christmas. he was 12. My limit is three...they are high maintenance. I thought serious about not getting another pup. However, Nelson is adorable and I couldn't resist. Hard work, though! Once you've had a setter, you're hooked.

 

[Lesley Gilks]

Bog depth is an interesting question - some people build them 18 inches deep; mine is 4 feet deep. Others are anywhere in between. We built ours deep to accommodate the centipede and snorkel. People will tell you that too deep is going to be a clean out issue. In 8 years we have never had a need to clean out the bog. I've dug down two feet and the gravel is clean and not one bit smelly.

Our bog has a layer of softball sized boulders around the centipede. On top of that we have a layer of Aquablox. (I honestly don't remember how many... maybe four? Six?) On top of that we have another layer of the softball sized rocks, then a layer of river rock (about golf ball sized) then we finished with a layer of gravel. We did not use the tiniest pea gravel; ours is a bit bigger, maybe the size of a raisin? (Trying to use common sized items here to illustrate size!) I've never used oyster shells, but I know some people do for the reason you mentioned.

Your goal should be to turn over your pond 1.5 to 2 times per hour. I'm not a pump pro but I do know that how high you need to pump the water comes into play with sizing the pump. Maybe someone else will chime in here with some advice on that.

As for your basin, that's another math equation. You need to consider what will happen if you turn off the pump (or the power goes out) - will the pond continue to empty into the basin and for how long? You want the basin big enough to hold that amount of water AT LEAST. Ours, like I said, holds 1000 gallons. When we get rain, it gets filled up. When we lose water due to evaporation, the water level in the rain exchange goes down, not the pond. We built it big so we could always hold more than we need. We have our sump pump plumbed into the rain exchange to capture that water as well. Occasionally there is too much water due to heavy rain, but we have an overflow that will slowly reduce the level.

Hope that helps!

I've got my head around the bog filter but as you say the basin for the negative edge is the issue. It may be easier to install a skimmer box but it won't look so good. The reason for the negative edge is because of the slope and and I thought it would look dramatic falling out of the pond from the reverse side. I have several large plants that will need to be removed so they will leave a substantial hole so thought I would utilize that rather than filling them in. TheAquablocks hold 32 gallons so are you saying I would need 10 to have a large enough reservoir for the pond? I think with the bog filter, as long as you drain it regularly, you shouldn't get sludge build up. You see them sticking pumps down the sump to flush out the muck from underneath and the Aquablocks held reduce sediment. I was thinking once every three months or is this too often? I wasn't planning on installing an automatic rain harvesting system, although we do have a water butt that I plan on using to top up the water manually. We're in North Wales and it rains here, a lot!

 

[Lisak1]

You need to be able to calculate how much water will continue to flow out of the pond in order to calculate how big the overflow needs to be. In theory you could construct it so no water - or very little water - leaves the pond once the pump stops, but that was a bigger construction challenge than we were up for. Our liner from the pond overlaps into the rain exchange and the water continues to flow under the rock that forms the waterfall at that end until the water level is beneath that edge. We foamed it originally, but that only slowed the water down, it didn't stop it. And since we have plenty of storage underground, we don't worry about it. We have 32 Aquablox in our rain exchange.

The other option is to build it as big as you can, or want it to be, install an overflow, and then just accept that you may occasionally lose water when/if the pump goes off. As long as the water has somewhere to go other than flooding your yard it's not an issue.

 

[Lesley Gilks]

On one of the YouTube videos, they mention introducing air into the centipede...is this necessary? I plan on using an air pump around the pond to introduce oxygen. The fish seem to like it and it makes sure there are no dead spots.

 

[Lesley Gilks]

I'm going to need something to house the fish in when the pond is re-vamped. What do everyone one else use? I'm thinking of setting up a quarantine pond afterwards so I have somewhere to put them if I need to.

 

[Lisak1]

On one of the YouTube videos, they mention introducing air into the centipede...is this necessary? I plan on using an air pump around the pond to introduce oxygen. The fish seem to like it and it makes sure there are no dead spots.

Hmmm... interesting question. How did they suggest doing that? We don't have any aeration in our centipede and I've never heard that's an issue. Aeration in the pond in general is important - the fish do seem to like it but it also helps keep the pond healthy.

 

[Lisak1]

I'm going to need something to house the fish in when the pond is re-vamped. What do everyone one else use? I'm thinking of setting up a quarantine pond afterwards so I have somewhere to put them if I need to.

If you're able to set up a full time quarantine pond, that's ideal. But people also use above ground pools as temporary ponds.

 

[j.w]

Full time would be great but temporary plastic wading pools or blow up ones are easy to set up when needed. Keep away from sharp dog claws and cover w/netting.

 

[addy1]

Welcome to our group of pond lovers!

Stock tanks make great pond/temp ponds

 

[j.w]

Hey and couldn't you just keep the stock tank up and running as a permanent quarantine pond as @addy1 keeps hers going for her lotus and fancy wiggle butt fish too.