We recently got a 2000 gallon outdoor pond going, which we will use for plants and fish. We didn't realize it, but it was filled with water that had gone through the house water softener. So, pH was greater than 10, very low calcium, and some alkalinity. We have used buckets of pH down powder, as well as pond salts. We still are at pH of over 8.5, with not much cacium (about 50 ppm). Also, the pond seems sudsy. Plants seem to be making it, but frogs died within a week. I was wondering of I added concentrated sulfuric acid (lab grade), if that would get me to a good place and then may never need it again. Is this adviseable? I am not sure if I need any more buffering, as the alkininity is fine. But, if necessary could add something else. Finally, do you think when the pH and calcium are correct, that the sudsy appearance will go away?
steve
I'm not sure what the sudsing is from. What chemicals is in your water softener? Ours replaces calcium, etc. with sodium which doesn't change the pH. Your softener would have to be powerful to alter the water so much. If the water has okay alkalinity, then you can use sulfuric acid. I would dilute it first into buckets and spread it evenly around the pond. Add some, wait a while, check the pH, and repeat if needed. You don't want to overdose and crash the pH down. Some people have ponds that do function at a pH of 8.5. If the frogs died at that pH, there may be something else in the water quality that killed them. Frogs are very susceptible to anything that's off.
Whether or not you'd need to add acid again in the future would depend on a few things. First, if you top off with the same water again, the same thing will happen. If there's another source for the high pH, that won't go away. For example, if you used any mortar or cement in or near the pond, that will raise the pH. Finally, the pH may not be stable if the water is too soft or low in alkalinity. If you have the ability to get water from your house source without going through the water softener, I would test that water for pH, hardness, and alkalinity. If it is better, I suggest a water change. I hope it works out!
I have also installed a diffrent pond in my yard and have this sudsing problem going on.I drained the pond all the way and it did not seem to matter,I have city water with no water conditioner or anything else.I am having a real problem with the ph as well. I cannot seem to get it to come down.I seeded my filter to try and jump start the biological side of it.I did that a week ago so other than that I am to puzzled with this foam problem.
What all is in the pond? What kind of liner and rocks? Any cement or caulking? Any ornaments? Runoff? Certain rocks may cause foaming such as limestone. Cheap liners (non-pond liners) can also cause problems. You should aerate the water well to get rid of the chlorine from the tap water if you're not adding a dechlorinator/water conditioner. What is the pH out of the tap and what is in the pond? Some rocks and cement may raise the pH.