The following is a downsized version of a 55 gallon sand and gravel filter used in koi ponds where exceptionally clear water is needed for viewing koi. The original full sized one by Steve Joneli aka Birdman can be found here. I take no credit for this. I simply downsized Steve's.
http://www.koiphen.com/forums/showthread.php?68132-Birdman-s-Sand-Gravel-Filter
It follows a primary filter that takes most of the solids out. In my case it's DIY sieve filter in a drum stacked on top of a DIY moving bed filter before the water goes up through the sand and gravel filter. A bottom center drain from the fish tank goes to the sieve filter as does a surface drain, also know as a Cornell Drain although mine is a DIY smaller version.
Steve also does a good job of showing how to build his full size version step by step, which is similar to my downsized version except for the specifics mentioned below.
Mine was built from a 30 gallon drum for a lower flow rate of only about 15 gallons per minute (900 gph) due to the fact that my lower flow rate probably wouldn't be enough to use for backwash a full size 55 gallon drum. Steve's unit runs at about 40 gpm.
Both use air in conjunction with sending the flow out of a waste drain on the side to backwash.
Steve uses a full size blower while I use a shop vac on reverse flow to agitate the solids that that are trapped in the media.
I will be using mine for 150 gallon circular tank I will be hatching trout eggs in and rearing them to fingerling size before planting them into a flow through pond in the spring.
Perhaps this may be of interest to some of you?
Parts for the manifold:
The bottom manifold before final gluing: (There are holes drilled in the bottom for air to come out of to agitate the media for backwashing.
After gluing:
In the tank with the vertical air pipe glued in place and a grate on top to keep the stone above the manifold. Also shows the exit pipe (highest) and the backwash pipe (lowest). When in operation the top pipe is open.
http://www.koiphen.com/forums/showthread.php?68132-Birdman-s-Sand-Gravel-Filter
It follows a primary filter that takes most of the solids out. In my case it's DIY sieve filter in a drum stacked on top of a DIY moving bed filter before the water goes up through the sand and gravel filter. A bottom center drain from the fish tank goes to the sieve filter as does a surface drain, also know as a Cornell Drain although mine is a DIY smaller version.
Steve also does a good job of showing how to build his full size version step by step, which is similar to my downsized version except for the specifics mentioned below.
Mine was built from a 30 gallon drum for a lower flow rate of only about 15 gallons per minute (900 gph) due to the fact that my lower flow rate probably wouldn't be enough to use for backwash a full size 55 gallon drum. Steve's unit runs at about 40 gpm.
Both use air in conjunction with sending the flow out of a waste drain on the side to backwash.
Steve uses a full size blower while I use a shop vac on reverse flow to agitate the solids that that are trapped in the media.
I will be using mine for 150 gallon circular tank I will be hatching trout eggs in and rearing them to fingerling size before planting them into a flow through pond in the spring.
Perhaps this may be of interest to some of you?
Parts for the manifold:
The bottom manifold before final gluing: (There are holes drilled in the bottom for air to come out of to agitate the media for backwashing.
After gluing:
In the tank with the vertical air pipe glued in place and a grate on top to keep the stone above the manifold. Also shows the exit pipe (highest) and the backwash pipe (lowest). When in operation the top pipe is open.
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