WATER TEST RESULTS: PLEASE DEMYSTIFY -- IN SIMPLE TERMS

[Mmathis]

KH, GH, pH....... Help me understand how these work. Below are the results I've gotten so far, so maybe use them as examples.

2 1/2 weeks ago, I started wth fish & plants in my 100 gal. stock tank. Results were: pH - 7.6, KH - 4 (drops), GH - 8 (drops) [Ammonia - 0ppm, Nitrite - 0ppm, Nitrate - 0ppm].

A week later, after moving everything to the pond: pH - 7.6; KH & GH not done [Ammonia - .25; Nitrite - 0; Nitrate - 0].

A week later, [algae bloom] : pH - 7.6; KH - 4; GH - 7 [Ammonia - 0; Nitrite - 0; Nitrate 0].

Pond is about 3200 gal. SKIPPY is 100 gal. Have in-pond plants, and 11 small goldfish.

Tap water tested today: pH - 8.2; KH - 4; GH - 6.

Where do I stand and what does it all mean?

 

[addy1]

Here is some good information on pond chemistry, might help you figure out how you are doing.

http://users.vcnet.com/rrenshaw/H2Oquality.html

 

[crsublette]

Hmmm, with a pH of 8.2, then I would think your water would be at least 6 dKH ((dKH = degrees KH ... basically, one drop equals approximately 1 dKH )) I bet everything is ok with your tap water, just an observation.

I ran into this situation with my water. I had a 4 dKH and 8.4 pH. Turns out that my phosphorus level was quite high. After some reading, turns out the a very high volume of the phosphorus element can cause an increase in pH. Only way to remove phosphorus is water change, algae/plants, or chemical binders. So, I increased my water change and everything was ok, pH back down to ~7.7. KH is not the only element that can change the lower end of the pH scale; actually, turns out there are alot of elements that can change pH, it just depends on their volumes, and dKH is the main one. So, if your dKH is low and pH high, then likely there is something else in the water causing the pH to go up. If ya want to go through the hassle, you can add stuff to increase GH. GH brings the top end of the pH scale down. I often find water changes the easiest route. There might be something else in your tap water that is causing the change in your pH. I bet everything is ok, just an observation.

Total volume of KH available is dependent on water volume. A 3200 gallon pond has more KH available to be consumed than a pond with 435 gallons.

KH will naturally lower as your good nitrifying bacteria excrete nitric acid as they are consuming ammonia and nitrites. So, KH consumption is dependent upon how much your good guys must process. This is why very slow release KH products such as oyster shells are used in water. Also, I have read that some macroalgae excrete compounds that can increase KH, but these type of macroalgae mostly live in pHs above 9.

For more info, the one of the better forum threads I have found is Of course, we must talk about Hardness.


Good you are curious about all of these "weeds" (the details ). This info will be useful when you want to really push the limits of your water's volume ecosystem capacity for fish and other aquatic life.

 

[Mmathis]

Finally starting to understand...... The relationship among all the "things" in the pond is SOOOOO complicated, and I have no illusions of ever understanding it all. But in very simple terms [it's been too many years since I had any chemistry], KH is the ability of the pond water to buffer against drastic pH changes. The higher the KH, the less likely there will be "crashes." Guess it's like a safety net -- or layers of bubble wrap: the more bubble wrap there is, the less likely an object will be severely damaged.

 

[fishin4cars]

KH, that's a pretty good understanding. PH, That changes more when KH is low. PH will swing during the day some. the hotter and the more gases put off the more it will naturally move. be sure and try and check the water about the same time each day. morning can be quite different than evening. All the water chemestry is good to know. But the key factors you have to know. KH is your buffer, You need it up to keep PH more stable. Koi and Goldfish can handle a ph of 6.5 to over 8.5 the more stable at one # the better. So if your averaging 7.6 that's really good. The 8.2 is still well within the "GOOD" but that's a pretty big swing in a 24 hour period so it's actually kind of a bad reading. getting your KH up would help so that the swing isn't as bad. As discussed in another thread. Oyster shells are the easy way to get the KH up slowly and stablize it.
Sorry for all the underlining. It started with this post and I can't seem to figure out how to change it back to normal and i was in a hurry to get back out to the project.

 

[Mmathis]

The 8.2 is still well within the "GOOD" but that's a pretty big swing in a 24 hour period so it's actually kind of a bad reading. getting your KH up would help so that the swing isn't as bad. As discussed in another thread. Oyster shells are the easy way to get the KH up slowly and stablize it.
Sorry for all the underlining. It started with this post and I can't seem to figure out how to change it back to normal and i was in a hurry to get back out to the project.

I think the "8.2" reading was my tap water, not pond water. But the last check I did yesterday, the pond was up to 7.8 (I do check same time of day). Since I kept getting the same reading of 7.6 all the time, decided to start checking with the bottle of "hi range" reagent. The "low range" reagent stops at 7.6....

BTW, checked my kits for expiration dates and only info I could find was lot #. I was getting suspicious because all my readings have been "0 ppm" (well, except once), pH the same. Well, tap water was different, now that I think of it. Just thought you were supposed to have variations in ammonia, nitrite, & nitrate levels. Pond is just at 1 month old and all I've had is one mild algae bloom and now cola-colored water. Fish are thriving & growing, plants look great. [knock on wood]

OYSTER SHELLS: is there a min/max amt to use (3000-3200 gal)? How often do they need to be replaced?

 

[sissy]

I put in a lot of bags in moving water and in my pool floaties and I put almost half the 50lb bag I buy at tractor supply and it will just desolve and thats when you need to replace it .I buy the dollar store bags and fill them half full ,they get to heavy after that .

 

[Mmathis]

Does TRACTOR SUPPLY sell oyster shells? I need to call them and pay a visit. Was going to order some. Thanks, SISSY! Kinda thought they dissolved, but didn't want to sound TOO MUCH like a newb if they didn't

 

[fishin4cars]

Tractor supply here sells them for $4.99 a bag. I think it's a 5# but not certain on that. I use a bag a pond. They also sell a 50# bag as well. I hear others using lots larger amounts. My KH stays in the 120-130 range, My GH stay's at 100-150. After a rain it will dip down some for a few days. It never really needs replacing, just add some new to it once every 6 months or so. Now how fast it dissolvels will vary room one pond to another. your test kit will help you determine how often and how much to add. On your ammonia and nitrite. those are really the only two you need to test for right now. If you check daily or at least every other day you'll see a climb in ammonia, probably over .50ppm. Once that happens a few days later the nitrites will start to climb and the ammonia should fall back. after you start getting these readings then you'll start watching for nitrates. Your reading will stay at 0 until that happens. It could start in the next few days, it may take another 30 days depending on the ammnia and waste load being produced. MOST ponds start cycling in about 6 weeks and will start showing some nitrate readings at about 8-9 weeks, But again. that isn't set in stone. Lots of variables to consider. The more plants you have the less nitrate reading you may get. Plants use nitrates and can lower the readings to a point it appears there is a zero reading. This is rare in ponds that don't have large amounts of plants some where in the filter or stream, bogs, etc.

 

[Mmathis]

Trying to add plants as much as possible. The turtle area is sort of a mini-bog [no comments ] right now, 'cause I have a several-inch layer of pea gravel on the "shore" area and have stuffed it with parrots feather and numerous other plants. Have a "T" shaped spray bar coming from the pump that is adding extra water into the turtle side -- it's like a little shower and hopefully is helping to keep the water circulated [one day want to convert that to coming from underneath, but for now it's fine].

I keep buying plants and then tell myself that I've gotten enough. Then something else catches my eye. Now that I can actually see the bottom of the pond [yea!], I can see the oxygenators that I sunk -- have lots of different kinds of those -- and they are looking good. They're likely glad now that they will get some sunshine, now that the water has cleared some.

 

[sissy]

I buy the big bag and just store them in a tote in the basement and it is used for chickens to make there eggshells harder .I also use a combo of kitty litter and crushed shells to put in my pots for the plants .

 

[Mmathis]

Water check today, 100% A-OK! Yea! Ammonia, nitrites, nitrates all at 0ppm. PH stable at 7.8. KH & GH stable [don't recall exact results, but are the same, with KH actually up by 1 number]
. :banana:

Water is crystal clear and colorless [to the eye]! Now you can see that we installed the liner with the writing showing -- well, maybe that was intentional. Wanted the fishies to know their liner was "fish safe!"
:goldfish: :fish2:

 

[Mmathis]

About to leave for TSC for some crushed oyster shells [pH spike], and guess will change out some water when I get back [for the ammonia]. Pond is 5 weeks old. Does this look about right, or at least close to what you would expect? The ammonia has gone up & down a few times, but nitrite & nitrates are staying at 0ppm.

3200 gal with about 15 small/med. sized goldfish (largest may be 1-1/2" to 2" long), dozen or so snails, tadpoles, and box turtles that I'm not even sure are "using" the pond water. Tons of plants!