Gravel filer bucket for a koi pond - how to clean it and how to turn it off/on

[vodkin]

I bought a property with a koi pond and want to make sure I understand how the pond's filtration system works. It looks like it has not been cleaned/replaced in a long time. I attached two photos. There is gravel under algae - but you can hardly see it, it's so dirty.
1. How to clean it?
2. What is the knob next to it? I am troubleshooting water loss, and I know that the water loss only happens when I turn on the pump that pumps water for the waterfall. Somewhere along the pipe apparently splits - one line goes to the reservoir from which waterfall originates, the other goes to this filter. Maybe I can prevent water from going to the filter by turning this knob and see if water loss continues or not.
Thank you very much.

 

[Lisak1]

Well turn the knob … see what happens!

 

[GBBUDD]

I that filth/dirty water of yesterday's description has graduated. Today we recognize that while it may be very dirty what we find to be unattractive and of no value. We have learned that this is home to mother nature's millions of year of evolution.

Bacteria microbes diatoms etc etc live in these areas. Recently it's been discovered that the decaying gnleaf is what may many call dinner.

It's been kn I wn fir a while I e now that the old sponge filters should never be thoroughly cleaned nor should I uld t hey be washed with chlorinated water. These filthy sponges etc are probably what Is making your pond sucessful.

 

[vodkin]

Well turn the knob … see what happens!

sure, that's what I did, turned it 90 degrees, but nothing happened. I initially thought it would maybe stop water to be pumped into the filter bucket so I could narrow down the problem to the waterfall, but there was no change. If this is a standard construction I thought maybe someone knows what this knob is supposed to do. Thanks!

 

[j.w]

@vodkin
Someone may know what that knob is for but not me, sorry

 

[mrsclem]

It looks like a shut-off valve. Can you dig down and see what pipe it is connected to?

 

[vodkin]

I that filth/dirty water of yesterday's description has graduated. Today we recognize that while it may be very dirty what we find to be unattractive and of no value. We have learned that this is home to mother nature's millions of year of evolution.

Bacteria microbes diatoms etc etc live in these areas. Recently it's been discovered that the decaying gnleaf is what may many call dinner.

It's been kn I wn fir a while I e now that the old sponge filters should never be thoroughly cleaned nor should I uld t hey be washed with chlorinated water. These filthy sponges etc are probably what Is making your pond sucessful.

I hear you. But I know that this gravel filter has not been cleaned for 3-4 years. I wanted to know what is the right way to clean a filter like that. Underneath the very fine algae (I assume it's algae - it looks like it can be scooped but it's not) is gravel, not bioballs.

 

[GBBUDD]

First thing I'd do is check the water flow. See if it's restricted.

To clean fill a masons tub or similar with pond water take out the media and swash it around In the water . You just want to remove the heavy sediment not make anything look new again . That sludge to us is invaluable life to your pond microscopicly .

 

[vodkin]

First thing I'd do is check the water flow. See if it's restricted.

To clean fill a masons tub or similar with pond water take out the media and swash it around In the water . You just want to remove the heavy sediment not make anything look new again . That sludge to us is invaluable life to your pond microscopicly .

Thank you. Would you elaborate on possibility if flow is restricted? As far as taking out the media - do you mean gravel?

 

[mrsclem]

If you can scoop the gravel out and then place it in a mesh bag, cleaning it would be easier. If that filter has not been cleaned in that long, it's possible that that knob is a drain for the filter for cleaning and the drain is clogged. You don't want all the sludge from that filter to get into the pond.

 

[GBBUDD]

The flow rate does it appear strong or weak."