Too Much Filtering?

[clark kent]

1000 gallon pond, 4000 gallon / hr pump, Pondmaster Proline 4000 pressure filter. Waterfall feature. Runs 24/7.
There have only been 8 small/medium sized goldfish in the pond. I don't feed them. They eat bugs and what algae forms on the bottom.
The only plant in the pond is what looks like a water iris.
Water chemistry is excellent. Ammonia, nitrites, nitrates are all always practically nil. PH is steady at 8.5. (I keep the kH at about 125 with baking soda.)
The pressure gauge on the filter always stays at about ~3-4 PSI. I never have to backwash or rinse the filter, although I occasionally do because I'm told you're supposed to. Rinse water does come out a little dark for about thirty seconds.

The pond water always stays clear enough to see the bottom. The fish thrive. (There are now ~ 14 fish, and they are growing.) The iris is not doing so well. It looks for all the world like it is not getting enough nitrogen.

Is this pump/filter overkill for these few small goldfish? As the goldfish continue to grow and multiply can I expect the nitrate levels and filter maintenance to rise?

 

[mrsclem]

It may be overkill right now but as the fish grow and multiply so will the waste. Just enjoy the way things are now, most pond keepers have the exact opposite problem. If your iris is potted, you can always add fertilizer.

 

[Mayank]

1000 gallon pond, 4000 gallon / hr pump, Pondmaster Proline 4000 pressure filter. Waterfall feature. Runs 24/7.
There have only been 8 small/medium sized goldfish in the pond. I don't feed them. They eat bugs and what algae forms on the bottom.
The only plant in the pond is what looks like a water iris.
Water chemistry is excellent. Ammonia, nitrites, nitrates are all always practically nil. PH is steady at 8.5. (I keep the kH at about 125 with baking soda.)
The pressure gauge on the filter always stays at about ~3-4 PSI. I never have to backwash or rinse the filter, although I occasionally do because I'm told you're supposed to. Rinse water does come out a little dark for about thirty seconds.

The pond water always stays clear enough to see the bottom. The fish thrive. (There are now ~ 14 fish, and they are growing.) The iris is not doing so well. It looks for all the world like it is not getting enough nitrogen.

Is this pump/filter overkill for these few small goldfish? As the goldfish continue to grow and multiply can I expect the nitrate levels and filter maintenance to rise?

No such thing as too much filtering IMHO

 

[AlyssaFish]

Filter systems do not remove nitrogen from the water--they only convert it to a form that is not as toxic to fish (nitrate). So, your plants are getting all the nitrogen the fish are producing (assuming it's not getting consumed by algae or something.

You can add pond fertilizer tabs to the soil that your iris is in (assuming it's in soil and not gravel). You could also try feeding your fish to produce more waste.

 

[clark kent]

Yeah, I get the part about the filter assisting bacteria in converting ammonia to nitrites, and the nitrites to nitrates. Every surface in the pond is covered with a dull green/brown soft textured mat. That's what the fish are eating. It must be algae, but I can't identify what type based on the pictures I've looked at. Would that algae explain why the nitrate numbers are so low?

That algae isn't very pretty, but I guess it's better than the kind the makes the water green. The water is clear and the fish are happy, so I'm not inclined to rock the boat by changing anything. I'm just trying to figure out why I'm not experiencing the exact opposite problem like most pond keepers have.

 

[mrsclem]

Low fish load and over filtration. I sold off a bunch of koi several years ago and my bog plants went yellow. Not enough fish poo!

 

[GBBUDD]

Depending how long and if the algae looks like peach fuzz on the rocks or is it a couple inches long

 

[clark kent]

I'd say more like peach fuzz.

 

[GBBUDD]

Welcome to a well balanced eco system

 

[clark kent]

Welcome to a well balanced eco system

Thanks. I see now that it's just the cycle at work. The the fish poop, the fish poop releases ammonia, the bacteria in the filter indirectly converts the ammonia to nitrates, the algae consumes the nitrates, the fish eat the algae, repeat.

This is what the algae looks like. What kind is it?

 

[GBBUDD]

very hard to tell but it look like a good vacuuming will remove that if its what i think it is

 

[clark kent]

Please humor me. What do you think it is?

 

[Mmathis]

Dead algae?

 

[GBBUDD]

I think its a mix of c algae with sediment covering it / fish poop, dust, and dirt.

 

[Faebinder]

No such thing as too much filtering IMHO

See above.