Testing Kh And Gh During A Cycle

[CJH0825]

I currently bought a kh and gh liquid test kit. A little confused. I'm setting up a new 55g tank ( fishless cycle ). When I test the KH, the color of the water will turn from blue to yellow is what the directions say. I have gone as high as 12 drops and it has never turned blue. Am I doing something wrong?

 

[TaurineLittle]

You don't get the reading from when it turns blue, you get it from when it turns yellow. so if you've added one drop to the test tube and its gone yellow straight away then you have below 50ppm gh or kh (which ever you tested for). so if you add a drop and its blue, keep adding drops until it turns yellow. the number of drops you added to make the solution turn yellow is you reading for kh and gh. And make sure that it is bright yellow, not a greeny yellow. If you are unsure about the colour, stand the tube with the solution ontop of a white peice of paper and look down the tube with the lid off.
I hope this helps Don't worry it took me a while to get the hang of this test kit as well haha

 

[CJH0825]

But I've never had it turn blue or yellow

 The directions say to add 1 drop, the color of the water will turn blue then keep adding until the color turns yellow ( shaking in between drops ). Mine stays clear even at 12 drops

 
That's for the Kh

 

[TaurineLittle]

That is really odd which brand of test kit is this? API? Shake the bottles before hand? Strange problem, maybe take the test kit back to the lfs and have their water tested with it? Sorry I dont have any other ideas other than that...

 

[CJH0825]

That is really odd

which brand of test kit is this? API? Shake the bottles before hand? Strange problem, maybe take the test kit back to the lfs and have their water tested with it? Sorry I dont have any other ideas other than that...

Yes, it is API Liquid. Problem is, I bought it on Ebay because none of my lfs carry this stuff. LFS say there is no need to test the water for it, But if you buy a fish from them and it dies, You return the fish and have to give them a water sample and they test for it

 

[eaglesaquarium]

Just take your sample to the LFS and have them test the water and give you the results not just the standard "your water is fine".

Tell them you want specific values.

 

[CJH0825]

Just take your sample to the LFS and have them test the water and give you the results not just the standard "your water is fine".

Tell them you want specific values.

I have done that, problem is they use the test strips, Which I don't trust. I'll mess around with the tests until I can manage to get some kind of color.

 

[eaglesaquarium]

Fair enough... but if that's what they use, then that's what they will use when you bring in the dead fish, right? 
 
 
As for the kit - check the expiration date.
 
Test again.  Its been a while since I ran that test, but its possible that your water is extremely soft.

 

[TwoTankAmin]

Just a heads up. GH is really not important during cycling. It is more important in terms of the fish etc. that will go into your tank.
 
The KH is relevant here because it is a good indicator of the availablility of inorganic carbon which the bacteria need to convert ammonia and nitrite. KH is measuring carbonates. During a cycle you want to keep the kH up - at least 3 dg (3 drops). Maintaining this level (or higher) means there should be no stall or slowing from this.
 
KH is tied to pH, in order to change the pH one also has to change the KH most times. During a cycle the bacteria can use up the available KH which will stall the cycle in twi ways. One, no carbon and,two, no KH means the pH drops drastically. And at around a pH of 6.5 ( or a tad lower) the cycle tends to stall.
 
The first thing to try in order to restore pH and KH which has dropped due to cycling is to do a water change.

 

[Essjay]

With the KH tester, when you add the first drop the reagent is very dilute so the colour looks washed out whether it is blue or yellow. Take the top off the tube, stand it on something white and look down through the liquid. You should see a tinge of colour doing that. My KH is 3, and even after 3 drops the reagent is so dilute the colour looks washed out.