Pump Advice

[robynfali]

Hello again guys, after some pump advice now.

pond stats

2m by 2m by 1.2 metre at deepest point (small shelf on one edge)

I have 7 2" Koi in there at teh moment, and am trying to work out what power pump i need.

Is one that does 9000lph powerful enough, it is going through gravity filter and UV box, but am still getting an algae problem, not as much as before I got some floating plant stuff to shield sunlight.

[site admin]

Hi,
I tend to work in 'ft and inches'
So your pond is 6.5ft x 6.5ft x 4ft deep, which is 169cu ft x 6.25 gallons
1056 gallons. If you use a 9000litre (2000) gal/hr pump.You will turn the pond over twice a hour, which I think is too fast. The thing you must try to do is get water retention time in the filter, the longer the water spends in the filter the better.If the water is going passed your UV too quickly it cannot do its job.
But if the flow is too slow, you will get muck staying in your bottom drain run.
Also your stocking level is very low to produce the right amount of ammonia to seed your filter.
Maturing a pond takes time and can be 1 year or more.

Dave.

[robynfali]

How many more do you think i should put in then? just concerned as they grow over time, obviously when they get too big, then they will be sold/passed on.

I only got 7, well 8 if you include a fantail because I was not sure how many it would take.

[site admin]

Hi,
The safe stocking level for a well filtered pond is about 100ins of koi to a 1000gallons, which equates to 5 x 20in koi.
I have 6 koi up to 22ins in just on 1100gallons which I feel is on the limit.
But as they grow I will have to move them on.
Your 2in babies will take a long time to grow if the pond is unheated,
for effect you could do with a couple of about 10-12ins.
It is just finding a balance for your pond and filter system to keep your water parameters just right. This is the important thing for a healthy and visibly clear pond.

Dave.

[robynfali]

Thanks for that, i will try and get some more.

The water is actually lovely and clear, its more so the waterfall and the sides of the pond that are a bit algaed, maybe i am being a bit too fussy and expecting the sides and waterfall to remain perfectly clear?

[site admin]

Hi,
There is a member of the NWKS that is moving on some koi of about 12ins, not tremendous quality but good healthy koi, for around the £10 mark, he just needs the room. He lives in the Glan Conwy area.

Dave.