I think my previous thread post could have make a mistake on the ph...
Not sure it is because i am colour blinded to see the colour wrongly when i took the liquid measurement before changing the water...
Today when i measure using a newly bought ph meter, it is showing ph7... and when i do a liquid test again, i think it is showing ph7 also... or am i having colour differentiation error ?

Is this ph 7 ?
Photo%2018-10-12%2010%2047%2057%20PM.jpg

or ph 7.5 ?
Photo%2018-10-12%2010%2048%2032%20PM.jpg

Ph meter showing 7.0 (yes i have calibrated with the solution provided)
Photo%2018-10-12%2010%2043%2045%20PM.jpgPhoto%2018-10-12%2010%2043%2045%20PM.jpg

Using the ph meter, the stingray tank is showing 6.5.. and is the same result i got using the liquid tester.