500 gallon koi pond, liner 18” deep and in full sun.

[Laurie Ridgely]

Thanks for your input!
I am a nubie. Our pond is small and in direct sun. We have one 8” koi and 8-10 2-3” goldfish and koi. We want a pressure filter with a UV light— is this the right kind of filter for our set up? We have a small submerged filter box attached to our pump but it is not able to handle the job and our water is pea soup. Our pond is needy and our funds are not big.

[Orlando]

Thanks for your input!
I am a nubie. Our pond is small and in direct sun. We have one 8” koi and 8-10 2-3” goldfish and koi. We want a pressure filter with a UV light— is this the right kind of filter for our set up? We have a small submerged filter box attached to our pump but it is not able to handle the job and our water is pea soup. Our pond is needy and our funds are not big.

First, welcome to the forum. I recommend you post pictures of your system from the filter you have running now to the information concerning the pond. You're going too get information very valuable from bringing shade to the pond, ideas on filtration and all other things that are going to be of value to your pond. All start by adding a picture of a shade sail I installed for some friends a while back for their 700 gal goldfish pond.


Ps; I need help with the picture don't know why it's upside down, be patient Laurie help it's on it's way, thanks in advance.

[gray cat]

The shade sail looks great Orlando. Nice solution to their problem.

[Laurie Ridgely]

Thanks so much for your reply. I would love a sail but would have to convince my husband, lol. I will try to post pics soon!

[Laurie Ridgely]

IMG_1543.pdf

Here are photos of our little pond and existing pump and filter. What do you think? Will a pressure filter give us clean water? Thanks in advance for your thoughts

[Noahsnana]

First thing you need is aeration...18in deep at the temps in MD this week (80's) they will need air. Are you sure that preform is 500 gal ? Even if it's an aquarium air bubbler would help

[Laurie Ridgely]

Thank you for replying Noahsnana, we have 2 bubblers and the waterfall— is that enough? Yes! It will get hot this week.

[Noahsnana]

That's good... I didn't see the air in the pond
Anything you can do to create shade will be a plus

[Laurie Ridgely]

Orlando, I really like the sail you installed. Can you tell me more about the posts you installed? Are they 12’ 6x6? How much shade is enough, like how many hours? My pond is very alkaline so having water plants to shade now wont work.

[Orlando]

Those are 10' x 4" x 4" only went down 36" and they are supported with quick kreete the sail was 10' the owner was also concerned with the amount of shade his plants would receive, I believe something like that would be more than enough for you.

[Laurie Ridgely]

Those are 10' x 4" x 4" only went down 36" and they are supported with quick kreete the sail was 10' the owner was also concerned with the amount of shade his plants would receive, I believe something like that would be more than enough for you.

Thanks! Also, I know I don’t have enough filtration. Would you say we need shade and a better filter? Do you believe we can get a some what clear pond with a pressure filter like this one? TIA!

[*Ci*]

Thanks! Also, I know I don’t have enough filtration. Would you say we need shade and a better filter? Do you believe we can get a some what clear pond with a pressure filter like this one? TIA!

I would say yes, this filter will help your pond. It is mostly the UV feature that will kill off the pea soup algae. I also agree that this preform is probably not 500g, and you could be overstocked with your 11 or so fish. Keep an eye on the parameters as the fish grow.
What are the approximate dimensions of the pond?

[Laurie Ridgely]

I would say yes, this filter will help your pond. It is mostly the UV feature that will kill off the pea soup algae. I also agree that this preform is probably not 500g, and you could be overstocked with your 11 or so fish. Keep an eye on the parameters as the fish grow.
What are the approximate dimensions of the pond?

Hello and thanks! It is quite possible I have over estimated the size of our pond- I cannot measure it exactly right now but would say it is 8’x5’ and 18” in the middle with a shelf around half of it. Can it hurt to have a filter too big?

[*Ci*]

Hello and thanks! It is quite possible I have over estimated the size of our pond- I cannot measure it exactly right now but would say it is 8’x5’ and 18” in the middle with a shelf around half of it. Can it hurt to have a filter too big?

No, in most cases over filtering is a good thing. One negative could be that the pump flow might create a current that is too much for the fish, but that can always be diffused with waterfalls, spraybars, etc.
If you ever empty the pond and refill it, you can meter the water as you fill to get an exact volume. You can also measure water volume using salt:

https://koiorganisationinternational...te-pond-volume

Knowing your exact water volume is useful for medicating or adding other chemicals to the pond.

[Laurie Ridgely]

Thanks so much for your help. I have ordered the new filter and we are looking into possibly putting up a sail. Fingers crossed it will work!

[lrowland]

If you cannot make a sail work you can also get a large patio umbrella. Here is the one I have over my pond:


From Amazon: https://www.amazon.com/gp/product/B07DKYM2JC

[cindy]

Another option is floating pond plants like hyacinth or lettuce in hula hoops

[Laurie Ridgely]

If you cannot make a sail work you can also get a large patio umbrella. Here is the one I have over my pond:


From Amazon: https://www.amazon.com/gp/product/B07DKYM2JC

Thanks Irowland, I love your pond, very nice. We did use a patio umbrella til a gust of wind took it down. Now we have a pop up awning trying to determine placement for a permanent solution. We’ve had the awning up for little more than a week. How much shade should we be shooting for? Thanks again!

[Laurie Ridgely]

Another option is floating pond plants like hyacinth or lettuce in hula hoops

Thanks Cindy— I want to have plants but right now the ph is about 9 and everything I’ve tried dies. Do you know of plants that can handle the higher ph? I’m hoping with shade and the stronger filter the ph will come down!

[aquaholic]

Unless the water flow through the UV is extremely high, I predict your UV filter will not be able to keep up with green water algae production rate if your pond is in full sun. It will kill the algae going through the UV filter but too much of the pond water will remain green. And if you do have high flow rate, you need a longer length and higher power UV lamp (or two) for effective kills. UV is less effective when water isn't clear so green water algae cells reduce rhe light transmission hugely. So be sure to size your UV filter capacity appropriately. Amalgam high intensity lamps in stainless steel chambers from home UV filtration suppliers may be more cost effective than "pond " UVs.

Adding floating plants, shade cover, will definitely help.