fertilizing with Koi pond water

[Sawdust]

I was wondering if using some rain water and some of the water from the pond filter (when I clean the filter material) would be good for the orchids.

[rbarata]

It will be difficult to answer without a proper chemical analisys.
My oppinion is that it might not be harmful with the proper dosage. You can increase the amount of pond water if you see good results (ot, at least, no damage)
Read this as there more things to consider.

[estación seca]

The main problem is many ponds have very high levels of dissolved salts, because they are continually refilled as they evaporate down. Splash some of the pond water on a glass and let it dry outside. Does it leave white mineral spots?

[Dimples]

Use it on outdoor, in-ground plants. They’ll love it. Excess salts will be leached out by rain. Limits the potential odor issue too.

[Leafmite]

I had an ornamental goldfish pond (for thirteen years) and always used the water for all of my houseplants, including the orchids. Never had quite the same, fantastic growth since I gave up the pond hobby. If you are using a concentrated version, just dilute it. Any use of fertilizer with potted plants requires flushing or changing the media now and then (I prefer flushing the medium. Every summer, I water the plants until the water pours out of the bottom.). Good luck!

[WaterWitchin]

I owned a water garden store before retiring, and have had a koi pond in my yard for over 35 years. When I still moved orchids outside in summer (quit about four years ago) had a pump and watered the orchids directly from the pond. About seven months out of the year.

Like Leafmite, plants looked great and it was just so easy. Wouldn't use the water from cleaning filter medium...no plant in a pot wants all that yucky stuff the medium is filtering out. The sediment is just going to clog the medium. Save that for pouring around plants in the ground.

[Waterdog111]

As a long time breeder and keeper of aquari. , I would say that the nitrates and or nitrites in disolution of the water would be at a level where you shouldnt need any additional fertilizers and it should be very rewarding. You will definently not be the first to grow plants and aquaria in combination to compliment one another.

[Ray]

Some friends of mine and I used to be into aquaria, and we had a water-changing device that would jet a fine stream of water into the tank while siphoning out an equal volume. It was great - no issues with temperature or water chemistry "shock", and the output hose was great for watering my tropical plants.

One day my buddy was doing that, and fell asleep. I believe "whacky tabacky" may have played a role.
His livingroom flooded, as did the one in the apartment below.

He found a new apartment shortly thereafter.

[Waterdog111]

Was that coersed