Should I be concerned about absent KH?

[SheWhoConquers]

I am new to hobby so I never paid much attention to KH, but in my search to discover why I can no longer effectively keep floating plants, I have been testing and analyzing my water a thoroughly and discovered my KH is basically non-existent. I haven't bought the liquid test kit for KH yet, but on both the Tetra and the Coop test strips I test consistently with a brightly colored zero indication. I was surprised because with my limited knowledge of GH and KH I assumed having hard water meant I would have in the least some registerable amounts of KH. I mean I don't even have just hard water, I have SUPER hard water. Coop test strips give me a royal purple every time 😂 I am pretty sure my water is basically a brick out of the tap. So adding crushed coral or wonder shells sound counterintuitive to me when all I want is registerable KH.

And just to remove any tank factors out of the equation, the KH is non-existent out of the tap. So weekly water changes seem to do nothing but add zero to zero. 

Now on to PH concerns...currently I am running peat moss in my tank and the lovely thing about KH being on hiatus, I can lower my PH pretty easily. PH is around 6.8, down from my normal average of 7.4. It actually only took me, maybe two weeks to get there approximately. And my concern is that maybe I shouldn't be playing with PH if I have no KH. It feels like I got in a car to drive in a city with no traffic lights? So while on one hand I can go as I please, the danger of something going horribly wrong is possible as well, unfortunately.

So basically I guess my questions are whether I should just keep doing what I am doing regardless of KH absence? Can you just supplement KH without adding more brick to my brick water? And should I even be adding peat if I don't have KH on the premises to police?

 

 

[Jess]

"Should I just keep doing what I am doing regardless of KH absence?" - If you've been doing it for awhile and you haven't noticed any problems, then yes.  Are only the floating plants dying?  Do you have others that are doing fine?  Mine started dying when there weren't enough nitrates in my tank water (it was around 10-20 ppm); they started to thrive when I got the nitrates around 30-50ppm.  (I have a very heavily-planted, very lightly stocked tank, and my floating plants are red root floaters).

1. Have tested both the water in your tap (or whatever water you use for water changes) AND your aquarium water? 

2. Do you use any kind of aquasoil substrate?  If you do, your KH should always be close to 0 and that isn't a problem; it's a bit complicated but the aqua soils take the buffering agents (which we measure as KH) from the water and "lock" them in the soil...they "soften" your water without causing crazy pH swings.

3. Do you have a water softener on your tap?  Also, you can try Googling for your city/county's water report, where they will report a KH range.  It should roughly match what the test strips say (from your tap), as long as you don't have something like a water softener installed.  

You can definitely have tap water that has high GH but low KH. 

Bottom line: if I were you, I would first want to know what are the parameters (pH, GH, and KH) of my county/city water vs. my tap vs. my aquarium.  This tells you where the "change" in KH is happening, if any.  If all your water is soft, but you have been running this tank for a long time with no issues, I wouldn't rush to do anything.  The floating plant die-off, absent any other problems, I don't think would be caused by low KH...it could be caused by a number of things.  My tap water, and the rain water I use in my tanks, both have 1-2 degrees KH and my tank parameters stay very stable (I also use an aqua soil, so my KH measures 0 in my tank).  If you are seeing problems then it could be time to consider some kind of intervention. I personally like tinkering with my water parameters as little as humanly possible...so if my tank parameters stay stable and my fish are happy, I don't care too much what they are. 

Note: I personally tested all my parameters with two kits - API and Tetra - while I was cycling my tank and troubleshooting water conditions.  I personally prefer API for GH and KH because it's a drop-based test (I forget the name of this kind of test at the moment).  You add one drop and shake, add another and shake, until you see a color change.  For very low KH/GH, the color change is very subtle...so you have to put it against a white backdrop.  Test strips are great for a quick check, but the API GH/KH tests can be a bit more helpful sometimes.

[SheWhoConquers]

I wasn't blaming the KH for the floating plants, just explaining how I even got to looking at the KH. And as far as aquasoils. I do use aquasoils. However, I removed this as a factor when I tested from my tap and received identical results.  And regarding alkalinity out of the tap, water reports for where I live are a bit convoluted because at any time I can receive a mix of water from three different intakes, two are similar, and one is noticeably different and I haven't been able to determine how and when I am receiving more of one than the other. But essentially, the minimum alkalinity reported than can come out of my tap  ranges 25 to 50ppm, max anywhere from 50 to 100ppm, and average is supposed to be 40ppm to 75ppm. 

 

The ranges are unfortunate, but this is what I am left with when I can't just call the water company and say, hey is my water composition 50٪ Baxter intake 40٪ Belmont intake and  10٪ Queens Lane today? So understanding what's coming through my tap where I live, according to my water department is not an perfect science unless I move about 10 miles north.

I do plan on getting the KH liquid test though for a more accurate reading and no I don't use water softeners.

Edited May 15, 2021 by SheWhoConquers

[Mmiller2001]

0KH for tropical fish and shrimp is no problem. As they come from waters with less than 1dKH to 0KH. Plants appreciate low to 0KH and a lower GH also. But definitely don't expect hard water fish to survive in those conditions. They won't.

I would imagine your floating plant issue is related to nutrients in the water, or a lack of. Floaters can be nutrient hogs. I would look into a good fertilization method and start learning that process. Light can be an issue too, even when so close to the light source.

The only worry you should have is fluctuating GH/KH TDS. We can cause pH to fluctuate without altering GH/ KH by injecting CO² and other ways. But with no outside interference, pH swing would be an indicator of an osmotic shift and osmotic changes is what can kill fish. 

If you are worried about having a 0KH; you can certainly raise it. Quite easily infact. You can buy potassium carbonate and dose it directly to the tank or in your source water. I buy mine off Amazon. Just make sure it's food grade. Calculators are available and you would just measure the amount needed and dump it in. While running peat moss, I would check KH weekly and add potassium carbonate as needed.

 

Edited May 15, 2021 by Mmiller2001

[SheWhoConquers]

8 hours ago, Mmiller2001 said:

0KH for tropical fish and shrimp is no problem. As they come from waters with less than 1dKH to 0KH. Plants appreciate low to 0KH and a lower GH also. But definitely don't expect hard water fish to survive in those conditions. They won't.

I would imagine your floating plant issue is related to nutrients in the water, or a lack of. Floaters can be nutrient hogs. I would look into a good fertilization method and start learning that process. Light can be an issue too, even when so close to the light source.

The only worry you should have is fluctuating GH/KH TDS. We can cause pH to fluctuate without altering GH/ KH by injecting CO² and other ways. But with no outside interference, pH swing would be an indicator of an osmotic shift and osmotic changes is what can kill fish. 

If you are worried about having a 0KH; you can certainly raise it. Quite easily infact. You can buy potassium carbonate and dose it directly to the tank or in your source water. I buy mine off Amazon. Just make sure it's food grade. Calculators are available and you would just measure the amount needed and dump it in. While running peat moss, I would check KH weekly and add potassium carbonate as needed.

 

I will definitely look into potassium carbonate, not too familiar with its use in the hobby. But I'm curious now 😁  I think I will have to supplement the KH because I'm looking to stock a 36 gallon and I don't want to further my limit choices.

[Mmiller2001]

4 minutes ago, SheWhoConquers said:

I will definitely look into potassium carbonate, not too familiar with its use in the hobby. But I'm curious now 😁  I think I will have to supplement the KH because I'm looking to stock a 36 gallon and I don't want to further my limit choices.

Works well and it adds potassium to the water column. 

[tonyjuliano]

15 hours ago, SheWhoConquers said:

my concern is that maybe I shouldn't be playing with PH if I have no KH. I

That would be chief among my concerns.

[SheWhoConquers]

49 minutes ago, tonyjuliano said:

That would be chief among my concerns.

Hah! Yeah I know...it's a risk. At this point I'm wondering if I should just go "create" my own water as much work as it feels that I must do to keep the fish and plants I want with tap water.