questions about pH and kH test kits..

[hebi]

hi guys,

i read up on EI method just now and found it pretty interesting so decided to give it a try. but firstly, i need to determine the CO2 conc. first. i know about using pH and kH to determine that, so i want to ask what brand is good to use? is tetra good?

another thing, i know these kind of cheaper test kits are usually not so accurate, as in you need to have a 'control' to determine correctly the results. may i know how do you do that?

[Shadow]

ph and kH table only work if you do not have anything that alter water cemistry, for example ADA soil.

I use SERA, so far so good. I was told last time to get the test from shop with air conditioner. Also don't forget to check the expiry date.

Accuracy wise, you can increase it by increasing sample quantity. for example, usually they ask for 5ml sample water, let assume for 5ml it take 2 drop to turn the color to yellow. If you are using 10ml, it will take 4 drop. So just devide the result by 2 for 10ml, devide by 4 for 20ml, etc.

[hebi]

ok. looks like i have to get one first before i can understand what you are talking about for the last part. mind pm-ing me where you get it and how much? i saw somewhere that a particular brand also provide test for GH.

[enhanzed]

how about the dymax submerged co2 test kit ? doesn't seem to work in my tank ... colour doesn't change at all

[Shadow]

for drop checker, make sure you use water with kH about 4. The instruction do tellling you to use tank water but some of us use ADA soil that make kH equal 0, thus it green all the time.

[hebi]

what about GEX soil? so i have to get 2 seperate test kits for pH and kH right? i read in a few threads that its possible to do without the kH test kit as only pH is needed to use the kH-pH-CO2 ppm table. however, if my kH is not 4, the test for pH will be inaccurate right? am i right to say that?

[Shadow]

yes there is a way measuring CO2 only with pH, it is one of the thread somewhere, but I forgot

GEX is similar to ADA, so you can't use the pH-kH table

If I'm not mistaken pH measurement should be correct regardless the kH value

[hebi]

thanks shadow. heng i never buy the test kit for kH, if not waste money. if i never remember wrongly, someone say before that i can just measure the pH of water with around 3-5ppm of CO2(ambient concentration?) and compare it with the pH of my tank water. usually a drop in around 0.8-1pH will mean around 25-30ppm of CO2. so this method can be use?

sorry me really noob with these test kind of things but since just got pressurized CO2 so decided to go all out, haha

[Shadow]

there is more than that, if I remember corectly, you need to blow your breadth into the sample water....I can't remember the detail, you can try to do search.

[enhanzed]

i use custom soil ( some japanese brand ) from sea view ... can ?

[Shadow]

ok found the link:
http://www.aquaticquotient.com/forum...ad.php?t=14976

[hebi]

thanks bro. i bought API test kit for pH yesterday and found out that it can only measure from 6 to 7.6. last night i took a small sample ok my tank water and keep stirring it follow by letting it sit over the night. this morning i measure the pH and it shows 7.6( or maybe even higher since thats the maximum it can show). then, i measure the pH of my tank which i already have the CO2 running since last night at 3bps. its shows 6( or maybe lower since thats the lowest). so since there is at least a 1.6degree change in pH, can i safely assume that the CO2 in my tank is at its optimum level?

last but not least, Merry Christmas everyone