Pre-Filter for Bog Filter? ??

[Julles]

In conjunction with my other question, for my proposed enlarged pond, I would still like to use the bog filter idea.  The problem I'm having with mine is that the pump takes vegetation and fish waste, grinds it up, and sends it through the hoses to the gravel pit of the bog filter.  Well, all this gunk settles to the bottom of the gravel pit, where it eventually clogs the holes of the PVC pipe (yes, even with water rushing out at the rate of 900gph). 

I've been having to back-flush the hose system twice a week to keep the flow going, and now, for the second time, all that gunk has pretty much blocked all the exit holes in the PVC pipe.

This causes all the water to come out at the last end of the PVC pipe, with enough force to actually "gush," and it has even overflowed the side of the filter, draining the pond.

I'm thinking that if I could get some kind of mesh filter on the system before it gets to the bog to catch the "solid waste", I could wash that once a week, and prevent any build-up in the bottom of the bog.

Any thoughts?  Do you think that would work?  If so, what kind of filter could I use?  I am afraid of having something outside the pond, because anything with hoses and openings so you can clean it leaves the potential for leaks.  Something in the pond would have to be fish-safe, and not take up too much room, as well as be easy to clean.

???

[CT]

How about a settling chamber before your bog then you just suck the settled gunk out with a shop vac or such? Or, don't they have protective bags to go around your pump as sort of a prefilter to keep leaves and things from getting into your pump? My pump has a foam prefilter attached to it already. It's kind of a pain to clean it frequently though. I'm sure others can give you better ideas but that's what came to mind.
Kay

[emm]

Hi Julles,

Would it help to raise the PVC up a little bit?  Think mine is about 3" off the bottom.  It rests on a bed of larger stones.  Think the holes are 1/4" but can't remember for sure.  I do know that I made the holes slightly larger toward the end of the pipe.  Also, the holes face slightly downward to encourage guck to flow out of the pipe.  I referred to a website that suggested these things - sure didn't come up with it on my own.  I think the site may have been Nelson Watergardens.

My gravel filter (bog) has been through 4 ponding seasons (I think) and hasn't given any problems or needed cleaning out yet.

Kay's idea of a settling chamber before your bog makes sense to me.

emm