Pond Boss Forums GENERAL QUESTIONS Water chemistry Ph of 9.5

Earlier this year I tested my new ponds ph and it was 7.6 before I started fertilizing. I applied the recommended amount of pond fertilizer. I have seen about 20 5 inch dead bluegill. I checked the ph and it was at 9.9 in the early morning a few days ago. I applied 100 pounds of aluminum sulfate and the ph is now at 8.9-9.0 throughout the day. Does anyone know how I can get it back to the 7's and why it spiked in the first place?

My first question is -- how are you measuring pH?

I'm at a point where I only trust litmus strips and certain water test kits.

I have several inexpensive to modeately expensive meters, and they seem to be very inaccurate.

Pet supply stores sell some pretty good aquarium water testing kits. I've found them to compare pretty reasonably with more expensive commercial kits.

Yeah I bought a cheap little yellow ph tested off of amazon for like 20$ so it's very likely it is inaccurate

I use hot tub strips and they are quite good.

P.S. what was the fertilizer you used?

That seems way high! I would go with faulty reading.

Which fertilizer did you spread? Any ag run off?

The only fertilizers that I can think of that might do that would be the ammonium-only ones. They can volatilize ammonia which would create a pH around there in an otherwise un-buffered solution. This is used to amend acidic soils.

I used sportmax pond fertilizer but I didn't get a bloom because of the very turbid water

Walked out to the pond this morning and saw another small bluegill on the bank. Once I took a closer look I could see he was still breathing so I put him back in the water. He just floated on his side while still breathing and twitched a few times every few seconds so I don't have a clue what's going on.

I'd suggest testing the ammonia, nitrite and nitrate levels. The ammonia and nitrite levels should be zero and nitrate levels very low.

Have any fish been observed swimming crazily? Spinning wildly and launching out of the water?

What is the turbidity from? Fertilizer is pointless without sunlight. With heavy turbidity, sunlight is blocked out except in the very upper part of the water. Fertilizer is adding to your elevated pH and, accumulating in the water. If clarity returns, you could have an explosion of plant growth to contend with.

I've got a guy from the extension office coming out sometime next week. So hopefully he can pinpoint the problem. Haven't noticed any odd behavior from the fish other than the small ones dying on the bank. Yeah I shouldn't have fertilized since I didn't have much clarity due to suspended clay particles.

I have heard to put bales of hay in the water to capture the suspended clay particles. You can retrieve the bales once they have cleared the water. I dont how how much help or hurt that does. I'm fighting a clarity problem in one of my ponds.

"Bales of hay" may work, yet it should be clean Barley Straw. It only works if the water chemistry is just right. First, a jar test needs to be done to ensure there is in fact, suspended clay, and that some other mechanical action like fish or wind and waves are not keeping the water muddied. If it is muddied from true, suspended, colloidal clay, the water in an undisturbed jar will never clear or have more than a tiny amount of sediment on the bottom. If the water is muddied by fish, cattle, wind, waves, the water will clear and the bottom of the jar will have a good amount of sediment on the bottom.

Barley and Gypsum both sometimes help clear colloidal clay, but are very slow and often do nothing at all other than cost you money. "Hay" will not help muddied water clear and too much could lead to very poor water chemistry, even a DO crash and fish kill.

For hay to be a "filter" like seen in construction sites, water has to actually flow through the bales to literally filter the water. Even then, it is very inefficient.

Alum is the one product that when applied correctly, works every time.

Rainman,
Not to hijack this thread, but we've got this problem at our fish hatchery. Fish, usually 4-6", will swim in a corkscrew pattern, like their equilibrium is out of whack. They eventually die off. What does this behavior indicate?

The guy from the extension office came out today and he believes that a huge algae bloom caused the DO levels to drop significantly causing the small fish kill. He didn't seem to concerned about the ph although it is still at 9.3-9.4. He told me to just keep running the aerator and not to fertilize for a while since my visibility is around 10-15 inch. I'll be keeping a close eye out for some more dying fish over the next few days. Thanks for everyone's help

Have you seen any fish piping at the surface?

Yeah I've seen them popping the top of the water but I thought it was feeding