Frequency of measuring ph, kh, PO4, NO3

[PeterGwee]

Hi guys! Wanna check with you guys how often you'll do testing for the above mentioned.

Besides that, anybody have trouble identifying NO3 level using Sera test kit? I did a test using that kit but the colour did not match any of the colour on the paper...it seems a bit off colour..not out of range in my opinion.

[David]

hi peter

it is good to check the level of your tap water KH so that you will know if it is going to generally increase or decrease the desired KH point that you have choosen. It may be good to check your tank KH every water change executed...you may need to wait for about 30mins or so before.

As for the PH, you may want to get the 'long-term CO2 indicator'..that is the one that you mix tank water with solution and stick it in your tank...how it works is that

Blue = insufficient CO2
Green = CO2 rich water
Yellow = overdose

as the solution works in conjuction to the KH level in your tank...this means that what every you determine your KH,the indicator will turn green at the PH where CO2 is at optimum point....this means that roughly....
KH 3 = 6.4 to 6.6
KH 4 = 6.5 to 6.7
KH 5 = 6.6 to 6.8
KH 6 = 6.7 to 6.9

As for the NO3 test kit, i have never tried the Sera ones.....

[eggz]

Hi Peter,

Sometimes, I have trouble with the Sera NO3 test kit as well. I get a very light green(yellow?) colour I think because my NO3 level was very low due to the low bio-load.

I wonder how much error these test kits permit? For example if we were to put an extra drop of one of the reagents, how much different to the results would it make? Oh and that grey powdery reagent doesn't help either.

Perhaps you might want to do two tests in succession, sort of to "sanity check" the first one

As for PO4, I only test this when I see more algae than usual....


eggz

[vinz]

Hmmm... I find the Sera NO3 test kit colours match much better then the JBL one. It's more obvious as the colours are stronger. I won't usually match, but it's close enough for me. Anyway, do you view from the top or from the side of the bottle? I think the top view is the correct one.

I measure pH anytime cos I have a pH test pen thingy. KH usually after water change but once I get an idea how much KH drops after each water change, I only test once in a while. PO4 and NO3 only when I start noticing more algae then usual.

[sherchoo]

Peter,
What colour did you get.... so far I have no problems with my Sera test kits.

David,
I kinda regreted buying the JBL CO2 kit. I have to change the solution at every water change. I would rather measure the pH and kH separately and compare it against the CO2 table if I need to know my CO2 level. The co2 kit don't seem to give correct values of CO2 level.

[David]

sherwin....not too sure about the JBL ones but the dupla are pretty accurate....dont need to change the solution on every water change as long as the KH level remain constant to what was originally placed into the capsule