Another Kh/gh Question


After checking out a number of the very informative posts on this topic, I'm not ashamed to say it still confuses me but it's nice to know I'm not alone there lol

Anyway, the only test kit I have at the moment that tests kh and gh is the API 5 in 1 test strips. According to these my kh is about 40 ppm and my gh is about 120 ppm.

On these test strips the kh measurements start at 0 but then goes 40, 80,120, 180, 240. The gh starts at 0 and then goes 30, 60, 120, 180. That's a lot of wiggle room for me to guess at what the kh and gh are actually at.

Is it safe to assume these are not the most accurate? What tests for kh and gh do y'all prefer that provide an accurate reading?

Since most suggestions for kh/gh levels are referred to in dh that was a whole other research topic since the test I have displays ppm lol again, thanks be to the very informative articles on THAT! So that means my kh is roughly 2.25 dh and my gh is roughly 6.74 dh, according to the conversion chart I found a link for in another post.

So aside from the question about everyone's prefered kh/gh test kits, since I can't remember where I saw a chart posted for ppm/dh readings that range from soft to hard water, I guess my main question is this - can I safely keep a betta with these readings?

If not, what can I do to get within range for a happy betta? Ph is always 7 on these test strips. NO2 is 0ppm and NO3 is 20ppm


These 2 videos on water harndness and pH should explain everything.

I've never tested my water's KH or GH.

I have very buffered hard water, that consistently runs a pH of 7.8.

As long as my pH doesn't fluctuate, I'm good.

Most fish adapt to the water parameters they are placed in, as long as its stable.

Is your water source the same as the local fish store?


Bettas are not picky and those water parameters are actually pretty close to perfect. The only potential issue is your KH which is really quite low (you want it at 4+). KH works as a buffer for PH (as you can doubtlessly see explained in the videos above) so you can get PH swings with a lower KH. It would be better to up it a little with some additions in your tank like crushed coral. Do not, I repeat, do not use KH+ products. Any of these 'quick fix' (PH/GH/KH +/-) products are terrible and cause unstable water parameters that cause cycle crashes and tank wipe-outs. I'm not being dramatic. You would be better off with the lower KH.

However, before getting worried about anything I would go and double check your readings with a liquid test. I understand the temptation to use the strips (I also have them and once relied on them exclusively) but they are just too inaccurate for GH/KH readings specifically. Some brand strips are actually just as accurate in their measurements as the liquid tests (which is why you will see them endorsed in videos) but that is under the presumption that you can read the colours right. Which is near impossible. When I relied purely on the strips I thought my source water had GH 7 and KH 10. Turns out, after buying a liquid test, the GH is actually 3.5 as is the KH. That's how wrong I was reading them.


I will have to ask my local PetSmart about their water source (after reading that article posted by a PetSmart employee, as well as some personal experiences, I am very tempted to only buy emergency meds from them going forward and only purchase plants and livestock online)
PetSmart is my only local option.

So I can add some aragonite and give that time to do it's thing while I wait for a new kh/gh test to come in, hopefully the kh will improve and stabilize in that time frame.


If its PetSmart, then it's the local municipal water supply.

Our local PetSmart had its entire aquarium display and filtration system removed and replaced with an all new setup last December.

They mentioned having a water filter on the supply side for sediment and a large UV system. I didnt get a chance to find out if an RO system is used or how their new sumps work.


I'll have to ask my local PetSmart next time I have a moment of weakness and go in to scour the plant section and look at their sad bettas.

I'm on well water and I'm fairly certain the system we're on here is older than I am and severely lacking general maintenance and upkeep.

I've had diatom issues since moving here and I know in most cases the cause would be some imbalance in my tank, which I'm not ruling out. However, I always have to wipe out a mysterious red/brown colored film from my dog's gravity fed waterer. but I digress...

I used the test strips this morning on the tap and tank water, added some aragonite and will test again tomorrow to see how much of a difference it made. Now to go search online for a liquid gh/kh test kit!


How long does aragonite typically take to make a noticeable difference in kh?

I realized I previously said my pH is always 7 but after going over my notes from past tests I realize now that I was mistaken and my pH is a consistent 7.8

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