Biological plant filter pond - What water rate change?

[Mitch]

Hello, I've got a 2 tiered pond system. 1500gal in the top and 500 in the smaller. After losing all my fish in the lower pond to a heron and to reduce my running costs I wish to turn my 500 lower tank into a biological plant filter connected to the larger (they're currently independant).

a few questions

What water rate change does the lower need, it's currently 3 times /hour though I am looking at keeping this as a spare because it uses the most power (6000l/h)

I do have 2 further pumps and filterboxes in the 1500gal pond each @ 5500l/hour, could I use these 1 in each

or

I do have another quite small pump intended for a small fountain/filter which delivers about 800l/hour.

lastly how much shall I stock the bottom with plant media? the water shall be cascading in from the top pond.

I have 18 medium sized koi, the pond is 7 years old and water quality is excellent and clear. No problems bar the Heron!

Any advice would be much appreciated.

 

[Waterbug]

Ponds don't really "need" any set turn over rate. The only case for turn over is to increase O2 levels and that is directed related to the fish load and amount of food fed. O2 is needed by the fish and also the bacteria that converts fish waste. If you go by popular vote you will find many people who'll say "minimum of once per hour" or "twice per hour"...you get the idea. That's generally all they'll say....not why...just "I do this, my pond is perfect, you should do exactly as I do". Many people will also attach their own personal feelings as fact like "turning over 7.23 times per hour makes the water clear" or "makes my hair thicker". It's as endless as it is entertaining.

How you stock the pond with plants depends on the plant and your goal. Some plants will fill a pond in a few weeks given just a few starter plants and good conditions.

 

[j.w]

Mitch

 

[addy1]

I have a 10 k or so gallon pond, my pump is 4200 gph, it does fine. You have enough pumps, set up your pond, get the plants going see which one does the best job.

 

[Mitch]

Thanks guys, trial and error never does any harm. Will keep you posted.

Mitch

 

[fishin4cars]

welcome aboard!