Pond Water Chemistry

[Notauser]

This year is first time in my backyard, by my pool, that I’ve got a pond with several levels of cascading water up and running. The cascades and water fall are made up of rocks and cement, with a PVC liner for the pond. I don’t have a filter right now just a pump that pumps water from the pond to the top of the cascades. I also am not planning on fish or plants right now. What kind of chemistry should i shoot for to keep a clean pond. It doesn’t have to be crystal clear like the pool but I don’t want stuff growing in there. I put a little bleach in it every few days when I add it to the pool but I am guessing without CYA it doesn’t hold. So where is a good starting point?

 

[DrewLG]

If you don't want algae, add algaecide. Use a product that's specifically for ponds, not aquariums or pools, and make sure it's safe for fish and plants -- you may later decide that you want some. I use these: MICROBE-LIFT ALGA16 Algaway 5.4 and API POND ALGAEFIX

There are also clarifiers/flocculants for ponds, to gather fine suspended particles into larger clumps that will fall to the floor of the pond. Again, use a pond-specific product that's safe for fish and aquatic plants. This one works well: API POND ACCU-CLEAR

 

[Notauser]

Thank you, nothing beats someone with experience. Do you run a filter? I've seen various ones at big box stores and online but without fish and plants right now I'm not sure I need one.

 

[DrewLG]

Do you run a filter? I've seen various ones at big box stores and online but without fish and plants right now I'm not sure I need one.

I do have a filter. But I also have fish and plants, and the pond collects a fair amount of debris from trees, heavy rain, bathing birds, etc.

I imagine you could run without a filter, at least for a while, if the environment around your pond is pretty clean. But I've only ever owned one pond, so I'm no expert.

Oh, one more thing. If your pond needs mosquito control, these work great and aren't harmful to people, pets, fish, or plants: Summit 110-12 Mosquito Dunks, 6-Pack, Natural

 

[koffey]

Question. Could you not just throw in some plecos into the pond and have them control the algae? With freshwater plants/fish in a pond, isn't it really just a big aquarium?

 

[DrewLG]

With freshwater plants/fish in a pond, isn't it really just a big aquarium?

It's a lot harder to control the water chemistry and temperature in an outdoor pond, so hardier species of fish and plants are usually required.

 

[Notauser]

How often do you treat the water with the algaecide? From the labels I've seen online they tell you how much product for how many gallons your pond is, but I don't see anything regarding the frequency of use. What kind of aquatic plants and life do you have? My wife would love to have a lively pond but I thought just getting it running and holding water was a win.

 

[DrewLG]

How often do you treat the water with the algaecide?

Instructions on the bottle say to dose weekly. But I only use it once or twice a year, when the algae isn't being kept in check by the fish and my normal maintenance.

What kind of aquatic plants and life do you have? My wife would love to have a lively pond but I thought just getting it running and holding water was a win.

Goldfish and one koi at the moment.



Waiting to see how big the koi grows before I get another. Plants are bamboo, water hyacinths, water lilies, etc.

There's a great koi and pond-supply store near me (Connie's Pond & Koi LLC) that's helped me a lot. If there's a similar store near you, they'll be able to recommend plants and fish for your environment and pond size.