I’m back again, and I am really at a total loss. At the point of throwing in the towel! (Aka that won’t ever happen) but I’m about there!! Anyway, the past 4 weeks I have been struggling with high ph. 9.6 evening and 8.8-9 in the am night. Before this all started I did what was hopped to be my last alum treatment after stabilizing the banks, but things went south from there. I think I used the wrong kind of hydrated lime, and that caused the initial spike. I lost 90% of my fish and since the pond has just gone down hill. I had high ammonia and nitrites as well as green water within days of the treatment. Presumably from the dead fish I couldn’t get out. Anyway rewind 3 weeks and my ph was still at the same high level, so I added alum to drop it down. It did and all was ok for a few days. I then added micro-lift algae remover along with micro-lift PL. I wanted to really boost the benif bacteria and try and rebuild the ecosystem. All stayed good for about 4 days then my ph went back up a little then the next day a little more and now I’m right back at the same high ph I was. Ammonia and nitrate and pitas are all 0, so that’s one thing I actually got right, but I can’t get the ph to drop… I was going to add baking soda, but idk how much ponds say 1/5 of an acre and around 4-6.5’ deep. I’ll attach a picture from before this nightmare started. Actually the pics are from the beginning of the downward corkscrew! I just don’t know what I’m doing wrong, I also didn’t mention prior but my hardness is through the roof but my alk is showing less than 20ppm. I didn’t add a lot of the “wrong” hydrated lime and only did the 50lbs alum to 20lbs lime, but idk if that is still in there and is just bringing it up. Please help. I really can’t drain it and start over as it’s fed from wetlands below. This has been Very discouraging and defeating.
I’m guessing it would be best to work with the cards you were dealt as far as PH. If it keeps rebounding, there is a waters source that will just keep overwhelming your adjustments. You would need to line and isolate your pond to prevent this from happening, and that may not be practical. There may be potential to use actual acid, like HCL, in a slow drip to compensate, but that seems more trouble than anything.
But first, understand where that is coming from and see if it can be controlled. A spring? Runoff?
NC - I am a rookie here and don't have tons of experience with water chemistry but....
"I also didn’t mention prior but my hardness is through the roof but my alk is showing less than 20ppm."
As I understand it - Alkalinity is the buffer on wide PH swings.
That said, my pond water is still new as the pond finished filling this year. I had some questions early on about adjusting PH, Alkalinity...and the advice I received was to let it balance and not make changes. I don't know at what point it's safe to make changes but new water is likely more volatile than an established pond. Frequent treatments would, in my opinion, not always provide the same results.
Personally, I would let it balance for a bit and check it again closer to fall. If you Alkalinity still seems low in say Oct....maybe that's a good time to make a small change. Again, let it equalize and check again in the spring....small adjustments if needed.
That's just me though....sorry I can't help more.
1.5acre LMB, YP, BG, RES, GSH, Seasonal Tilapia I subscribe to Pond Boss Magazine
I don’t think it’s an ecological thing, as my water was always on the lower end of the ph scale (6.2+/-) then I started messing with clarity & chasing that perfect # and just jacked everything up. Is there a good way to “start over” and give myself a blank slate without draining it? Draining it isn’t an option unless I use multiple pumps and just not practical as it is wetland fed from below. I think the incorrect hydrated lime I used is the only logical occurrence that could still be raising the ph.
No need to drain it, just wait for it to settle. If you can, measure parameters over time and plot it on a chart. That will let you know when things are stable.
