building a 55 gal biological filter

yep your probably right ...just wasnt sure what that was on the top ...but im sure i could find something to fit on there ...thanks koiguy .... by the way skippie filter is working well on front pond ...clear water !!

Like Koi guy said .
Just stick it in and tie it down..
I have had a cat get on top of my filter and knock it out

Koikeepr
this is as close as i could get to cut & paste

I also have a diy filter system,what kind of filter media do you use?I was told that I need to change mind to deer block which is fencing.What do you think?Oh I have lava rocks now.

The deer fencing would be better than the lava rock..
and a lot easier to work with
You can use most anything... cut up pipe, scrubber pads , bottle caps, the list is long

so, right doc. Lava rock is so difficult to keep clean thanks to all the nooks and crannies it has. And as light as an individual little stone is, they can sure as heck weigh a ton when you're trying to life 'em out of a barrel for a rinse!

I'd like to build a 30 or 55 gallon filter like yours to provide a prefilter for my bead filter. Right now I have a surface mounted bottom drain plumbed directly into an external pump which then goes into the bead filter. I put filter material into the bottom drain, but it's a pain to pull the BD and clean it.

Would it work to have the line coming out of the pond and going into the barrel at the top using your design. The water would go down to the bottom, come up through the filter material and then out through a 2 in. bulkhead at the top-side of the barrel. This would be connected to an external pump which is pulling the water out of the pond and then pushing it through a bead filter and back to the pond via a 2 in pipe through a UV filter and into the pond. the flow rate of the pump is rated at 4500 gph, but I don't know what it would actually be before it gets to the pump.

if you want to use a barrel filter before your pump youll have to encorporate a filter pit set up to PULL the water thru.

D&RW, we need a bit more info about your setup, is where koiguy is going. It would be lovely if you could send us a photo of exactly what everything looks like.

What koiguy is asking is your set up gravity fed? Typically, when you have a bead filter, it's because you don't have gravity in your favor since a pressure/bead filter can be put anywhere (up or below water level). Whereas a barrel filter--when you have an external pump--requires gravity flow to feed it. Otherwise your pump is "pulling" and not "pushing." Pushing is no good for an a pump--they are designed to push and not pull.

This is exactly why I had to dig my filter pit and punch a hole in the side of my liner, so the water would gravity feed from my retro BD to my barrel and then up to my pressure filter.

So, the question at hand is: does the water flow from your retro BD to your pump with gravity flow at the moment?

None of my system is gravity flow. Probably could have done that if I'd planned for it, but it would have mean some digging and running pipes through the wall too. Not the kind of wall that would have been easy to run a pipe through.

I'll have one external and one submersible pump, both around 4500gph. The external will draw from the skimmer which will pull water from a surface mount bottom drain and the skimmer weir at varying percentages depending on time of year. I need a filter between the line from the bottom drain to the pump--it is a direct line; the skimmer flow is filtered in the skimmer itself.

the other pump will either go into the "shallow" end using another bottom drain or over by the side/plant area. it will be piped over the wall to the waterfall. The waterfall is an Easy Pro Aquafalls box modified to use three kinds of media: matala, aquaUV bio media, and Savio ribbon. This is the primary biological filter. I have plumbed in a bypass at the top of the filterfalls using 4 in pipe so I can redirect the flow away from the waterfall in the winter via an insulated pipe back into the pond.

so what i think i need is some kind of inline filter between the deep end bottom drain and the external pump.