Overstocking with Increased Filtration

[TJeep_1999]

For a few ground rules let's just assume you have enough aeration and room for the fish to swim. We can also assume more frequent water changes will also be required. Finally let's also assume you're overstocking with 2-3 fish and not hundreds.

I know fish hatcheries have massive filters that let them overstock so I know it is possible, but what I'm asking is there some specific ratio? Ex: Pond Size / GPH Filtration = Number of fish? If the filter is large enough to handle the increased bio load it should be possible or is there something else I'm missing (Please note above caveats)? What's the science behind it???

Thanks in advance!

 

[Jhn]

You are shooting for 2x pond volume per hour in circulation. There are general rules people come up with 1 koi per 1000 gallons then 1 per 500 gallons after that. All these rules are general and what may work In One pond will not in another. Type of pond comes into play dkp, eco pond, etc. Using a box filter, a bog and plants...pond size is another factor. What fish are you overstocking with a big difference between a goldfish and a koi when overstocking.

Will say if you ar doing water changes on a pond to keep the water quality up, you are going to end up with dead fish and a mess for a pond. Ie if you are changing water to keep ammonia down because your bio filter is inadequate, this is going down a road to a mess of a pond. do you know what is in your source water, water changes in ponds can be detrimental depending on the reason behind the water changes.
There are no hard fast rules to stick to really,( other than don’t overwhelm your bio filter) there are many different methods to successfully keeping a pond

 

[poconojoe]

Any fish hatcheries I've visited or seen on TV tours all had natural river water constantly flowing through them, so I don't think they necessarily have huge fitration.

There's one near me that is built on a river where dams create each holding pond. I dont even think they have any filtration. I'll have to ask next time I go there.

 

[combatwombat]

I don't have answers to your questions unfortunately, but I agree w/ @poconojoe. Around here, fish hatcheries are exclusively built alongside streams and rivers, so they are open systems with very little water circulation. Hard to compare them to what we build unless you're building from a natural water source.

 

[TJeep_1999]

I know BlueRidge has open ponds like you state above, but also large holding tanks with a huge bio filter. I can't speak for other hatcheries, but I know they at least use both.

 

[TJeep_1999]

I know BlueRidge has open ponds like you state above, but also large holding tanks with a huge bio filter. I can't speak for other hatcheries, but I know they at least use both.

I think I'm derailing my own thread I guess my real question from above is that if the filter is large enough to handle the increased bio load it should be possible or is there something else I'm missing (Please note above caveats)? What's the science behind it???

 

[WaterGardener]

Yes, it's possible. If you have enough filtration to handle the fish load, sure, you can overstock the pond. Pet stores do it all the time with their fish tanks. But if there is an emergency and your power goes off and you have no water circulation and no aeration, there could be a big problem.

I have no idea of the science or how much more extra filtration you would need per fish, but I'm a firm believer in the more filtration the better. I have way more than is needed for my pond, but I don't need to worry that my fish will outgrow my filtration.

I have a large pressure filter and a shower filter. The water coming out of the pressure filter tests perfectly. It goes directly to the shower filter, which evidently is doing nothing at all, since it's being supplied with pristine water. But I like having the extra cushion, just in case. And I have 150+ goldfish in 6,000 gallons of water.

I know, I'm weird, but I'm used to it by now.

 

[mrsclem]

There are a lot of factors so no real equation. I have one pond overstocked with koi ,3500+ gallons. 3 large koi-20-24" , 8 12"koi and 15- 4-8"koi. I have a 2x11 bog running 1600gph, Savio waterfall filter, 3600gph and a 2 barrel skippy filter running 1600gph. I don't do water changes, just top off when I flush the filters every other week. I feed very lightly but have no plants in the pond so they do get fed several times a week.

 

[Lisak1]

I agree - it's possible, but you're walking a tightrope. One tiny wobble and you're plunging to the ground. And that's sad when you're hauling big beautiful dead fish out of the water. That's not the way you want to figure out "well, I guess that was TOO MANY FISH".

 

[mrsclem]

Been there, done that! I admit I don't test my water but after 30 years of keeping koi I know when there is something not right. I still plan on rehoming at least 2 of my big breeders as well as about half of the others, just not sure when .

 

[Tula]

I've seen koi dealers with large indoor systems set up. I've noticed they use flow through water systems, so constant slow water changes. The one I'm thinking of also utilizes large shower filters

 

[GBBUDD]

Like it has been mentioned Bovey there is no book for dummies you don't turn the nut to 90 foot pounds. It is not an exact science. Your water supply is much different from mine. Your feeding different food then I do. I have a better understanding then you may as to the condition simply from watching the fish. As well s the algae it is a tell tale sign when something is not quite right.

 

[Lisak1]

It is not an exact science.

Nailed it right there. Your X number of gallons and my same X number of gallons are two separate and completely different eco-systems. They both have fish and water, but that's where the similarity ends. What one considers "lots of plants" may just be the started pack for another ponder. Throw in weather conditions, what surrounds your pond (farm fields? highways? suburban yards?) and all the other uncontrollable factors and you see why there's no formula to predict what will work without fail when you're talking stocking a pond.

 

[Jimmy Gibson]

I agree with Lisak1 you are walking a tightrope….. I have a 3000 gallon pond….. with a Ultima Bio Filter, filter material in my skimmer and water falls, and a huge amount of plants growing in the pond. I was very exuberant in my first year…. I had a huge spawn, took in fish that people wanted to get rid of … ect….. things were great while the water was warm and plants were growing, but then cold weather came and my pond crashed big time. I only have one of my original fish. Now I have 7 koi that are all over 24” and one goldfish that will probably go 8” …. I don’t test the water, I don’t change out any water, all I do is backwash the filter once a week, add water when the level gets low, feed them once a day, and try to keep the plants from overtaking the pond. The whole gest of what I am saying less is better, you have bigger, prettier, healthier fish, with very little work or expense.

 

[TJeep_1999]

My water quality is always perfect. Zero ammonia, Nitrates, etc... I test the water frequently so I know it stays level. I overfeed (Every day 3 times a day) and arguably am over stocked with fish (9 goldfish) I only back flush once a month and no water changes. I'm actually a bit surprised at how trouble free the pond has been and was wondering if it was due to the extra filtering I have (cycles the entire pond 4 times an hour) or if there was something else going on that I was missing. It sounds like I might just have a perfect situation that has made things so drama free so far and the filtering is just one part of it.

Based on the above I'm guessing I'll have to eventually clear out some fish rather then waste money on upgrading the filter. Only thing I need to figure out now is if I get rid of some of them now before we get too attached or just wait to see if it ever becomes a problem as they grow.

Thank you for all the insight/advice!