Sorry, yet another question.
what are peoples views on todays way of thinking with regards to flow rates through the filter? Should it be total volume of water once every two hours or should we be thinking higher turn over? Obviously showers are some what different, but was thinking more Eazy Pod/Nexus/multibays!
Looking forward to what your views are.....
Flow rates for a filter and flow rates for a pond are not the same thing. - The following assumes normal to high stocking levels and feeding rates, because as with any general rule someone will come up with an exception.
Modern thinking is that a pond should be turned over through filtration twice an hour, but no less than every hour. So a 10K pond should turn over at 20K lph but no slower than 10K lph, any slower and unprocessed ammonia will build up in the pond.
Filter flow rates should be up to the rate stipulated for the particular filter .... i.e. Nexus 200 max flow rate 10K lph - so anything up to 10Klph is acceptable and the filter will work okay. Trying to turn over a Nexus 200 at 20K lph will either mean that the filter will overflow, the biological filtration will be ineffective or the mechanical filtration will not work.
So its turn pond over quickly , but ensure filter works at its optimal flow rate. So smaller ponds can use a single large filter or larger ponds need multiple filters.
That is an excellent explanation, I had not thought of the difference between the two requirements, I have checked the flow rate on my pond and it is approx 6500l per hour (the size of the pond) which is more accident than design as the more powerful pump i ended up buying was on special and was thus cheaper than the 6000l per hour pump i had my eye on.
So, in summer under heavy feeding load, would it, in modern thinking be better to fit a more powerful pump? my eazy pod will handle 10,000 per hour flow rate so could stick a bigger pump on it.
I thought that a pond turnover of every two hours was one of the old suggestions and have not heard that a pond shouldn't be turned over in less than an hour
That puts me in under and hour pond syndrome as both my systems turn over fairly quickly as the 500gln system has a flow rate of over 1,500 gallons per hour and my 4,500 gallon pond turns over in less than an hours as well.I am a believer of having a good turnover but as Chris has pointed out you can pull to much water through a filter which will impair its optimal performance and not only give clarity issue must more likely parameter problems as well.I used to run a bigger pump on my vortex system and found that i got a better performance when slowing the flow down so changed to another pump and it works a treat.So its not just a matter of putting a big or bigger pump on the pond to turn it over it about having the correct filtration and pump for the job.
Gazza, I think I said "twice an hour" or in other words every 30 mins ... Like you my puddle goes through a filter even quicker - every 20 mins - 500 gals at a turn over of 1500gals means your QT turns over every 20 mins or a 10K pond with a turnover of 20K means the pond turns over every 30 mins
I knew you was too good and young to have the old big bang theory of two hours and please accept my apologies for being such a Muppet and not reading the post correctly...........no wonder its time for my eye test
[quote="boogatee"]Flow rates for a filter and flow rates for a pond are not the same thing. - The following assumes normal to high stocking levels and feeding rates, because as with any general rule someone will come up with an exception.
Don't forget that taking thing to extremes, 1 fish in 100'000 gals will only need water movement if the surface area is a 1'00 sq ft.
So I wouldn't get hung up on turnover rates more the stock levels vs gallonage and the size of your filters.
What is your gallonage? how many fish do you have (size in inches) total your inches vs your gallonage and post it on here also what type of filter/s are you using?
I am sure that we can then tell you a good compromise for filter flow then you can work out by dividing the flow into the size of pond and get your turnover.
I hope this makes sense but I deal with a pond of 180'000 gals and can measure turnover in days rather than hours or minutes.
Do what you need to maintain healthy fish and worry more about the size of your filter after all you could like it has been said drown your filter by over-running it.
Hi Phil,
It;s very kind of you to help out. It's only a small growing on tank and QT of 500gls filtered by an Eazy Pod. It's pump fed by an Aquamax 5500 and by doing the timing a bucket test I'm turning over 931gls an hour. I was wondering if that was to fast and if I should put a valve in to create a by pass? I only have 3 X 5 inch koi in at the moment but will be adding more once I'm happy with the set-up.I'm also slowly bringing the temperature up to 18c. Also I'm planning to have a small BHM shower doing it's thing once I have built my small fish house.
For your stock level at the moment I would at least halve the flow because I personaly wouldn't think that the filters will mature at this level certainly there will not be any sustainable biomass in your filter for your bacteria to get their paws on.
if you put a divert valve on the pump send the residue of the water being pumped back into the tank and give it a bit of a flow, istead of just restricting the flow.
Maybe others would think diferent, give it a go and monitor the water quality.
This one wasn't but I put one in to keep the water sharp. I was looking for the picture I posted on here some 2 years back when I was looking for ideas but I think they have been relegated to the bin when Dunc had his restructure.
The pond in question does not belong to me i just look after it. It belongs to a nice old gent that use to own Littlewoods and only has 6 Koi in it and about 50 Golden Orfe. I have been trying to get rid of the Orfe but they breed to fast.
I think that this year we may have to look at glassing it because the liner is now in it's 15th year and showing signs of it's age.
filter flow rates
as both my systems turn over fairly quickly as the 500gln system has a flow rate of over 1,500 gallons per hour and my 4,500 gallon pond turns over in less than an hours as well.I am a believer of having a good turnover but as Chris has pointed out you can pull to much water through a filter which will impair its optimal performance and not only give clarity issue must more likely parameter problems as well.I used to run a bigger pump on my vortex system and found that i got a better performance when slowing the flow down so changed to another pump and it works a treat.So its not just a matter of putting a big or bigger pump on the pond to turn it over it about having the correct filtration and pump for the job.
... Like you my puddle goes through a filter even quicker - every 20 mins - 500 gals at a turn over of 1500gals means your QT turns over every 20 mins or a 10K pond with a turnover of 20K means the pond turns over every 30 mins 
