What to do when your plans for a dream gardenpond go awry? Build something else. I spent the last month building a spot to quarantine new fish before they go to our future large pond. Thanks to all who have posted here in the past and my previous failures I think it includes a number of improvements.
We already have one koi greenhouse, but don't want to just add new fish to it so a smaller one, 5 by 9 seemed the right size for smaller koi. Dig out was week one. Moved enough dirt around to bury just over half the pond.
Week two was all about the foundation. 500 figure 8 blocks, 200 bags of concrete and 40 bags of mortar were needed for the job along with some 1/2 inch rebar
I decided to liner and test the pond before finishing the foundation. I placed 30 feet of 2 inch abs with 1/4 inch holes every 4 inches. 8 to 10 inches of 3/4 river rock for the pond bottom. This will be a down flow design with a pump that will suck water into the bottom of the pond, basically a downflow bog for the whole pond. Then it pushes the water into the bottom of the side bog along with a second pump that pushes water to a pressure filter and second water fall located inside the bog.
Next was to finish the foundation and start framing and then change plans to move the upflow bog to the side at 30 % the size of the pond with 20 inches of gravel larger at bottom the pea gravel at top with 10 feet of abs with slits cut every 2 inches. This will give more space in the greenhouse.
Now into week three it was time to finish framing before putting up the walls. Then added a water fall rock along with testing my ability to seam liner with combo 2 sided tape and a final one sided over the seam. We choose panels with air channels to help with insulation.
Week 4 and now it is done. And we have added some new under 8 inch fish to grow out over the winter and add to our new outdoor pond next year (will be working on that over the winter with a build next summer). Final size, 4'10" by 8'10" by 42" deep (with rock) and then a 5' by 2.5' bog at 20" deep. Around 1200 gallons of water once we get it topped off. Just waiting for the water lilies to reach a little bit higher. Based on my experience with ponds, it should allow for up to 20 small finish or 5 to 10 medium. Not planning this for long term koi, but will likely keep a few in here long term if they stay on the small side.
Right now I have a 55 watt 1500 gph pump that pulls water from the bottom of the pond and pushes water into the bottom of the bog. Then a second pump that will eventually be a 2000 gph and 100 watt pump to pull water from the bottom, and push into the pressure filter and then an upflow water fall mini bog that falls on top of the main bog. I picked this design mainly because I had lots of left over parts from previous builds and it seemed to maximize the filtration and aeration with two falls instead of one. I can also easily clean out the pressure filter and it is a good way to clear garbage out of the pond a few times each summer.
Things I did better this time around.
1) Insulated panels for green house with limited gaps around framing and roof to keep warmer in winter.
2) pavers in floor instead of concrete (easier)
3) Figure 8 blocks for 100% of framing and pond. Much easier to line and build on. Took longer to make and cost more, should also help with insulation.
4) Larger Bog to Pond ration at 30%, likely more with the double bog design of an upflow bog and an upflow water fall.
5) Pond is essentially a down flow bog with 8 inches of 3/4 river rock and 30 feet of abs with holes. This should really increase the filtration of the system.
6) More seating in green house.
7) Used cut single ply panels to make the ridge and valleys, kept it clear and cheap.
8) Pre painted/stained black 2x4s really make it look better and should last much longer (I did this last time, but it is an important step that makes it work).
9) Wife found an awesome glass storm door.
Oh year, the wife as always did close to 50% of the work with me, not a solo one man gig here. She did not participate in the below section nearly as much as I did however ...
Things I messed up, koi are between the south sun and the seating area to the north. Should have reversed this to reduce glare. Cut the bog liner before having the water fall completed and ended up with a very limited amount of liner to spare. Did not pre set the foundation screws into the framing and attempted to use screws that were too small. Will have to fix this by drilling in better bolts this winter. Need a better way to install the ridges at the top, they are wavy because it was scary to be up on top of thin plastic with limited ability to stabilize while drilling pieces in. The first 2 piece H clamp that holds the panels together do not slide in place, they are hammered with a rubber mallet. Sliding them wasted over an hour before watching a video to learn the right way to install. It is hard to keep the figure 8 blocks straight and with only 1/4" mortar between each one. Walls are slightly different lengths, one went crazy and ended up being 5" too long because of excess mortar. Leveling them was also hard as the mortar seemed to thin in some spots and too thick in others, maybe a better base would have helped, but I did something wrong with the initial level and ended up having to add upto an inch of mortar as a final layer in some spots.
We already have one koi greenhouse, but don't want to just add new fish to it so a smaller one, 5 by 9 seemed the right size for smaller koi. Dig out was week one. Moved enough dirt around to bury just over half the pond.
Week two was all about the foundation. 500 figure 8 blocks, 200 bags of concrete and 40 bags of mortar were needed for the job along with some 1/2 inch rebar
I decided to liner and test the pond before finishing the foundation. I placed 30 feet of 2 inch abs with 1/4 inch holes every 4 inches. 8 to 10 inches of 3/4 river rock for the pond bottom. This will be a down flow design with a pump that will suck water into the bottom of the pond, basically a downflow bog for the whole pond. Then it pushes the water into the bottom of the side bog along with a second pump that pushes water to a pressure filter and second water fall located inside the bog.
Next was to finish the foundation and start framing and then change plans to move the upflow bog to the side at 30 % the size of the pond with 20 inches of gravel larger at bottom the pea gravel at top with 10 feet of abs with slits cut every 2 inches. This will give more space in the greenhouse.
Now into week three it was time to finish framing before putting up the walls. Then added a water fall rock along with testing my ability to seam liner with combo 2 sided tape and a final one sided over the seam. We choose panels with air channels to help with insulation.
Week 4 and now it is done. And we have added some new under 8 inch fish to grow out over the winter and add to our new outdoor pond next year (will be working on that over the winter with a build next summer). Final size, 4'10" by 8'10" by 42" deep (with rock) and then a 5' by 2.5' bog at 20" deep. Around 1200 gallons of water once we get it topped off. Just waiting for the water lilies to reach a little bit higher. Based on my experience with ponds, it should allow for up to 20 small finish or 5 to 10 medium. Not planning this for long term koi, but will likely keep a few in here long term if they stay on the small side.
Right now I have a 55 watt 1500 gph pump that pulls water from the bottom of the pond and pushes water into the bottom of the bog. Then a second pump that will eventually be a 2000 gph and 100 watt pump to pull water from the bottom, and push into the pressure filter and then an upflow water fall mini bog that falls on top of the main bog. I picked this design mainly because I had lots of left over parts from previous builds and it seemed to maximize the filtration and aeration with two falls instead of one. I can also easily clean out the pressure filter and it is a good way to clear garbage out of the pond a few times each summer.
Things I did better this time around.
1) Insulated panels for green house with limited gaps around framing and roof to keep warmer in winter.
2) pavers in floor instead of concrete (easier)
3) Figure 8 blocks for 100% of framing and pond. Much easier to line and build on. Took longer to make and cost more, should also help with insulation.
4) Larger Bog to Pond ration at 30%, likely more with the double bog design of an upflow bog and an upflow water fall.
5) Pond is essentially a down flow bog with 8 inches of 3/4 river rock and 30 feet of abs with holes. This should really increase the filtration of the system.
6) More seating in green house.
7) Used cut single ply panels to make the ridge and valleys, kept it clear and cheap.
8) Pre painted/stained black 2x4s really make it look better and should last much longer (I did this last time, but it is an important step that makes it work).
9) Wife found an awesome glass storm door.
Oh year, the wife as always did close to 50% of the work with me, not a solo one man gig here. She did not participate in the below section nearly as much as I did however ...
Things I messed up, koi are between the south sun and the seating area to the north. Should have reversed this to reduce glare. Cut the bog liner before having the water fall completed and ended up with a very limited amount of liner to spare. Did not pre set the foundation screws into the framing and attempted to use screws that were too small. Will have to fix this by drilling in better bolts this winter. Need a better way to install the ridges at the top, they are wavy because it was scary to be up on top of thin plastic with limited ability to stabilize while drilling pieces in. The first 2 piece H clamp that holds the panels together do not slide in place, they are hammered with a rubber mallet. Sliding them wasted over an hour before watching a video to learn the right way to install. It is hard to keep the figure 8 blocks straight and with only 1/4" mortar between each one. Walls are slightly different lengths, one went crazy and ended up being 5" too long because of excess mortar. Leveling them was also hard as the mortar seemed to thin in some spots and too thick in others, maybe a better base would have helped, but I did something wrong with the initial level and ended up having to add upto an inch of mortar as a final layer in some spots.
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