4dkh Or Tap Water?

[SuperColey1]

I did a silly test today really but it was because my CO2 drop checker was giving me such good yellow/light green that I thought I would make sure it was still good. (It was turning blue when I first mixed it)

I took 6ml of the following waters and dropped 4 drops of API ph test in them and the results were:

Tap - A lovely blue just like my dKH solution was when I first mixed it
4dKH Solution - Still blue but now a greeny blue
Tank Water - a nice green

Therefore can I summise the following or am I totally wrong in my thinking here.

The tap water must be a similar dKH as the solution was when I mixed it - i.e. 4
The solution has been contaminated even though it is in a sealed bottle? Maybe contaminated by the plastic of the bottle?
The tank reading is not accurate due to this contamination?

I am mixing some more now to do a further test on my Big bottle of 40dKH

So can I use my tap water rather than mix these substances seeing as it comes out the same colour as the 4dKH did at first?

Very interested

Andy

 

[Dave Spencer]

When you add the API drops to your tap water, it is the pH of your water turning it blue, not the carbonate hardness. You have tap water at the same pH as your 4dKH, but not the same carbonate hardness.

Both your tap water and 4dKH may be showing the same blue because they both have a pH above the top range of your test kit.

Dave.

 

[SuperColey1]

Dave

I catch your drift here but what about the solution differences.

2 months ago I mixed up 100ml in the 10 to 90 ratio and kept it in a small medicine bottle.

The first test came out a bright blue before entering the tank and eventually turning green.

This is the 3rd time I have used it but it now comes out the turquise colour.

So I mixed from the 490ml I had of the 40 solution 10ml with another 90ml and we have bright blue again!!!

Does it contaminate from the plastic over time?

Andy

 

[SuperColey1]

I think I have answered my own question now.

The tank water that was light green to yellow in the tank was sat in its wine glass for about an hour.

Went to empty them all out and clean them and it is now bright blue so maybe the solution isn't contaminated after all!

Worries over

Andy

 

[Dave Spencer]

Good stuff, it would have been surprising for a clean medicine bottle to leach anything in to the solution.

Dave.