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api gh test kit

1368 Views 9 Replies 9 Participants Last post by  DefStatic
this is the second test kit i have purchased in the last year. the liquid is supposed to go from orange to blue. it takes 3 drops to turn orange, and after 55 drops i am still orange. now i know their is no way i can have a gh of 900+. i tried the test strips and the moment it hits the water it instantly turns purple. is their a better way of testing GH?
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Hi allabouttheplants,

Welcome to TPT! I suffered for a couple of years with the API GH test kit and had exactly the same problem....it is difficult to see the color change even when looking 'down' into the test tube as they suggest. As I suffered the last couple of years I did some research for alternatives. Recently my API ran out and I purchased a SERA GH Test Kit from Aquacave ($10) and although it is not perfect it is 100% easier to read than the API Test Kit.
I had the same but went back to the easy to use but not too precise Jungle brand 5-in-1 strips from Wal-mart. I find that they may not be precise but a test I can read sure beats one that I can't read! After mixing a set of samples of known value, I found I might as well just spin a wheel to get a number for the API tests. It all looked purple.
I get the test strips from whichever on line store has them the cheapest. Usually 100 in a bottle for the same price as the stores sell for 25-in-a-bottle.

I do get odd results once in a while, but I can generally see the color change in the API test kit. But it is the first one to die of old age. Then, no matter how many drops you add there is no color change.

By comparing tests from prior weeks I can tell if something is changing in the tank. Not so much the actual number (I think we all agree the tests are not great at that) but the trend. If the water is gradually getting harder in the tank then I know to do bigger water changes.
Wash your tubes with DI/RO water. Then do a dilution of your tank water. A 1:10 dilution and. 1:100 dilution. That'll tell you what range you're in at least. My gH has gone up to 30 before because I kept topping off my tanks with tap water

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55 drops! Dang you have the patience of a saint! I'm not sure I could cap and shake a test vial that much.
I don't care for this test either.
You can invest in an alkilinity test. They make them for reef tanks, but the test is the exact same thing as GH. These tests will give you values in increments of about .4 GH. Yes, that is point 4. Very precise, but they cost about twenty bucks.
You can invest in an alkilinity test. They make them for reef tanks, but the test is the exact same thing as GH. These tests will give you values in increments of about .4 GH. Yes, that is point 4. Very precise, but they cost about twenty bucks.
Super late response, but Idk what I was thinking earlier. Alk tests correspond with kh, not gh. Sorry for the confusion.
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