Pond Boss Forums GENERAL QUESTIONS Water chemistry Do I mess with Alkalinity?

A recent Pond Boss article recommended pond alkalinity to be at or above 50 ppm. I had my pond tested and its alkalinity is 39 ppm. Knowing that if I raise the alkalinity more nutients will be freed, do I make the adjustment or let sleeping dogs lie? I'm inclined to "make the water happier" but don't want to tamper. The full results for the pool store water test are below.

Free Available Chlorine 0.09 ppm
Total Chlorine 0.09 ppm
Combined Chlorine 0 ppm
pH Level 7.2
Calcium Hardness 0 ppm
Total Alkalinity 39 ppm
Cyanuric Acid/Stabilizer 2 ppm
Copper 0 ppm
Iron 0 ppm
Nitrates 0 ppm
Phosphates 99 ppb
Total Dissolved Solids 0 ppm
Saturation Index -1.5

See if this helps you out a little.

SRAC 4606


I had some similar questions on a water sample we got back recently.

Boondoggles Water Thread

Hope it helps.

I would add some ag lime. Calcium and magnesium are the major constituents in total hardness. You have 0 CA hardness "Calcium Hardness 0 ppm". "Calcium is an essential element for fish, and moderate
calcium levels in aquaculture water aid in fish osmoregulation during stressful periods. As noted above, calcium is important for egg and larvae development." Ca (calcium) -Desirable range More than 20 mg/L Acceptable range More than 5 mg/L "

Makes sense on the calcium. I do want to be thoughtful about making a change to the pond chemistry and understand the likely consequences.

The pond is about 30 years old, 3/4 acre, and farily deep throughout with steep banks 7-11 ft. It is 100% runoff through a forested area of deciduous trees with a few pine. GIven the runoff being filtered through the forest there is little silting, but plenty of muck from leaves, branches, etc.

If I up the alkalinity, will I likely be fighting blooms that are not beneficial?

Do you have underwater vegetation in the pond?

Just me guessing but upping your alkalinity via ag lime provides a more stable PH, and the calcium hardness you are short. Higher quality water is more productive and as a result could result in a healthier fish population and blooms.

I guess the big question is....what are your goals for the pond?
- If you are happy with it...why change it?
- If you are looking for more from it, healthier water is a good starting point.

If you decide to lime, you are in full control on how much you add. Go slow, give it a chance to balance, monitor your results over a couple of months and then decide if you want to do more. I hear it takes a bit (month or two) for the lime to take effect.

I am a rookie here and just beginning my new hobby as a pond manager. I'm sure one of the other experienced fellas can help you if you decide more about your goals for the pond.

Good luck!

Might I suggest another water test by a pond service or state service provider before you add anything?

There is no underwater vegetation. The water gets too deep too quickly even thought the water clarity is typically 3+ft most of the time.

I did have a watermeal problem three years ago but a summer of monthly direct spray treatment (surprisingly) cleared it out. Haven't seen it since.

I am working to up the pond productivity. Installed an aeration system late last summer and have a texas hunter feeder installed. Managing a population of BG and LMB for size. I know getting large sizes for both is likely not possible, but will see what the pond tells me as I feed, catch, and selectively cull both LMB and the BG.