Need help with KH

[Frankyfish]

I have a API master reef testing kit but the instructions are very vague. It took 20 drops to get the water to change color. After that I dont know what to do. 20 is not on the chart. Tried to find some videos about it but the one I found just show them testing the water. I have no color chart for the Carbonate Hardness. I am just lost. Super new to saltwater and im cycling my 1st tank. Any help would be appreciated!

 

[Ron Reefman]

There is no chart for API alk testing. Each drop is 1.0dKH. If it took you 20 drops to get 10ml of water to change to yellow, your dKH is 20 which is crazy high.

Take a glass and have fill it with tank water. Now fill the glass with RO/DI fresh water (like your top off water). Now you have a 50% dilution of your tank water. Test it with the API kit and the color should change at about 10 drops.

It could also be your kit is defective or maybe expired? You could take a sample to your LFS or a reefer friend and test the water with some other kit (API or any other brand). Take your test kit as well and have them do a test with your kit and watch to make sure you are doing it correctly.

If you have more questions, please ask them!

 

[mike550]

I have a API master reef testing kit but the instructions are very vague. It took 20 drops to get the water to change color. After that I dont know what to do. 20 is not on the chart. Tried to find some videos about it but the one I found just show them testing the water. I have no color chart for the Carbonate Hardness. I am just lost. Super new to saltwater and im cycling my 1st tank. Any help would be appreciated!

Hi @Frankyfish couple of thoughts here

First, it sounds like your dKH is really high. I would definitely test again to make sure it’s not a testing issue. If you have a local fish store that can test your water too that’s a good backup.

Second, what salt are you using and are you starting with RODI water? I think RODI water has very low carbonate hardness. It might be that you have very “hard” water coming into your house.

By the way. You’ll learn quickly that API test kits aren’t great. As you progress you might look at other test kits.

Good luck!

 

[Ron Reefman]

Frank, don't worry about using API test kits. They work just fine. Ive been using them for nearly 20 years. I also use Salifert test kits and I find the API and Salifert kits give me the same results 99.99% of the time.

API kits are less expensive and do not measure down to fine numbers like most of the other kits. But that doesn't mean they don't work.