Do I have too many goldfish? How can I help this situation?

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Hello all!
I have approx 2000 gallon pond (water garden). At it's deepest, about 6 feet deep. Two waterfalls, air pump, UV light and skimmer, leaf basket, and a bio filter. Water moves from the skimmer back up through a bog filter down the waterfalls.

Since I added a new biofilter this spring, and started treating for algae, I have had an overwhelmingly full bio filter every time I go to rinse it. To the point that I'm wondering if I just have so much waste, or dead microscopic algae.
For the past month+ I have had to use my pond vac on my bog filter area and my skimmer area (both shallow) weekly(!) so I can get out the maximum waste I can. I've had some decent success getting the water as clear as possible (for the summer) - that is, until this week. We've had a 95 degree + week, so I've stopped treating for algae, and added a tarp to cover as much of the pond as I can.

Finally, I have approximately 40 fish, and about 2000 gallons. But I'm still struggling with waste management. Could I still have too many fish?

Here are some symptoms that I'm struggling with:
  • The bog filter seems to accumulate a new layer of dead micro algae (or pond waste) on a weekly basis. I currently have 3 pond iris in there, and they're not eating up enough waste.
  • Regarding bog filter - Is it possible I need more rocks? More plants? It's only about 3'x3' (this is also where the pumps come up). In the bog filter, when I vacuum, I sometimes find even darker gray/black spots below the top layer of dead green waste.
  • Because I've had to stop treating for algae this week (because it's been 95 degrees+ daily) the water has gotten greener. I have a bio filter + the uv light + bog filter - Is there anything else I can do? Barley?
  • My fish definitely had babies: I've seen some newbies join the pond. I'm concerned this will increase waste and I'll have a fish kill this summer (which I did have last summer as well).
Thanks for your advice, all. This forum has been so helpful to me, so I appreciate all your support to make our ponds beautiful and clear!
 

JRS

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When you say treating for algae-an algaecide, copper based? As you are aware, dead algae adds to the nutrient load, you may have bad cycle going, although removing the waste does help.

Any more details on your bog such as depth, gravel type, upflow? Three individual iris plants in the bog seems light, any room for more plants? Any pics of the bog and or pond?

Size of your fish? Lots of feeding also contributes to nutrients and algae.
 
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When you say treating for algae-an algaecide, copper based? As you are aware, dead algae adds to the nutrient load, you may have bad cycle going, although removing the waste does help.

Any more details on your bog such as depth, gravel type, upflow? Three individual iris plants in the bog seems light, any room for more plants? Any pics of the bog and or pond?

Size of your fish? Lots of feeding also contributes to nutrients and algae.
- Algaefix for the algaecide - Every 3-4 days (except on these really hot streaks)
- What do you mean by bad cycle?
- Bog pond is 14" deep, and only about 2" at the top covered with water and the iris bulbs. Gravel type not sure - Pebble size, mixed. Upflow from the savio skimmer.
- Some fish as small as 4", some as large as 10" - I feed twice a day, but they typically consume it all. Should I feed them less? They're only hungry in the summer...

Attaching some pictures from today (after pond vac + filter rinse). I expect it to be slightly clearer tomorrow, but we are having 100+ degree days this week so I can't do too much without risking oxygen depletion.
 

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AP1

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A question: is the water just running up over the top of the bog or is it moving up (or down) through the rocks in the bog?…Also, my planted aquarium instincts are telling me you should aim for much more planting as a long term goal
 
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It sounds like you’ve got quite a setup with your pond, and managing waste can definitely be a challenge. Adding a new biofilter and treating for algae might be contributing to the excess waste you’re seeing. It’s possible that the dead algae is clogging things up.

A few thoughts:

• Adding more plants to the bog filter could help absorb more nutrients and reduce algae. Have you considered adding different types of aquatic plants?

• More rocks in the bog filter could improve filtration.

• Barley straw is a natural option for algae control; have you tried it?


Also, with 40 fish in 2000 gallons, it might be pushing the limits, especially with new babies. Have you thought about rehoming some of the fish to reduce the load?
 

JRS

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Thanks for the pics, you have a very nice setup there.

What do you mean by bad cycle?
Just meant you have excessive nutrients fueling the algae, then killing the algae adding to the nutrients with only your pond vac and rinsed filter as nutrient export.

Definitely get that bog full of plants, many garden center plants that like wet feet do well in a bog if others are not available-such as hostas and canna lilies as well as others. As mentioned, any plant growth there will use nutrients that is fueling the algae. I have small 2'x3' bog full of cattails, which can run wild, but I have not had green water since in my ~1300 gallon system of goldfish pond and tubs with turtles.

Ever consider water lilies? Looks like you may have room in the pond and they provide natural shade.

I would do once a day feeding at most, you could even do less-every other or every 2-3 days without a problem, until your system improves
 
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You definitely need more filtration, whatever type you choose. You can't have too much.

I would back off the algaecide. Killing it is adding to the problem.
 

AP1

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I'll be curious to see the OP's reply to the question about the flow through the bog. If the water is just flowing over the top of the rocks (i.e. not down/up through them), then the bog is quite possibly not doing very much for the OP right now...
 
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Hello all!
I have approx 2000 gallon pond (water garden). At it's deepest, about 6 feet deep. Two waterfalls, air pump, UV light and skimmer, leaf basket, and a bio filter. Water moves from the skimmer back up through a bog filter down the waterfalls.

Since I added a new biofilter this spring, and started treating for algae, I have had an overwhelmingly full bio filter every time I go to rinse it. To the point that I'm wondering if I just have so much waste, or dead microscopic algae.
For the past month+ I have had to use my pond vac on my bog filter area and my skimmer area (both shallow) weekly(!) so I can get out the maximum waste I can. I've had some decent success getting the water as clear as possible (for the summer) - that is, until this week. We've had a 95 degree + week, so I've stopped treating for algae, and added a tarp to cover as much of the pond as I can.

Finally, I have approximately 40 fish, and about 2000 gallons. But I'm still struggling with waste management. Could I still have too many fish?

Here are some symptoms that I'm struggling with:
  • The bog filter seems to accumulate a new layer of dead micro algae (or pond waste) on a weekly basis. I currently have 3 pond iris in there, and they're not eating up enough waste.
  • Regarding bog filter - Is it possible I need more rocks? More plants? It's only about 3'x3' (this is also where the pumps come up). In the bog filter, when I vacuum, I sometimes find even darker gray/black spots below the top layer of dead green waste.
  • Because I've had to stop treating for algae this week (because it's been 95 degrees+ daily) the water has gotten greener. I have a bio filter + the uv light + bog filter - Is there anything else I can do? Barley?
  • My fish definitely had babies: I've seen some newbies join the pond. I'm concerned this will increase waste and I'll have a fish kill this summer (which I did have last summer as well).
Thanks for your advice, all. This forum has been so helpful to me, so I appreciate all your support to make our ponds beautiful and clear!
The general rule is that you can have one inch of fish for every 10 gallons of water. So how big are the fish in inches? So long as they are not over 5" long, it's not overstocked.
 

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