Twistofer
New member
I have seen various threads asking and commenting about the quality of marine aquarium testing kits. However, the quality of the kit, in some respects, is only as good as the person doing the test. I would like to take a moment to post a few things, which effect the quality and consistency of the results from almost any test. Taking a few moments extra to perform a few steps can really improve the marine chemist's results.
1) Preparation of sample vials and measuring equipment (syringes, beakers, graduate cylinders, etc.). Rinsing this equipment with RODI/Distilled water will help get rid of any latent chemicals, deposits and debris from your previous testing and storage of that equipment. Follow this by a good rinsing with your sample water. Don't dry the equipment, just use them with the sample that you want tested.
2) Measurement of samples, reagents, etc with syringes. Remember to do this the same way each time. In syringes, there will be an air bubble. This is the air in the tip of the syringe. You can do one of two things. Fill the syringe so that the bottom of the bubble is at the desired mark on the syringe, or fill it where the plunger is at the desired mark. I recommend the latter, because when the bottom of the plunger hits the bottom of the syringe barrel, the air bubble pushes out the last little amount in the syringe, giving you the "exact amount" of the solution you needed.
3) Measurement of samples, etc with graduated cylinders, pipettes, etc. A meniscus (concave surface) forms when measuring solutions. This is caused when the liquid adheres to the wall of measuring device. The bottom of this curved surface is the true measurements. (However, substances that do not adhere to the wall, such as mercury (not used much) will form a convex surface. You read the top of the surface in this case. Very, Very Rare).
4) Measurement with droppers and dropper bottles. The bottle/dropper is held "perfectly" vertical to form the drop. The drop falls off the tip and is not shaken or tapped off or even dipped into the test vial.
5) Swirling your solutions, rather than shaking them. Shaking can introduce air into the solution, which may alter the results. An old chemist's trick is to flick the test vial with your middle finger of your free hand. Make sure you mix the solutions for the full amount of time indicated in the instructions.
6) Cleaning your equipment. A thorough wash in warm, soapy water should be followed by a good rinse in regular water. Follow this with a thorough rinse in RODI/Distilled water. I don't recommend drying your equipment with paper towels, cloth towels, etc. These leave lint and other contaminants. Ideally, get some acetone from your hardware store and rinse the equipment out. Acetone dries very quickly and leaves no residue. If your equipment has caps, you can put them on, but don't close them tightly.
7) Care of your Reagents/Chemicals. Some kits say that you can put the unused portions of titrating agents back into their respective containers. IMO, this is the quickest way to contaminate those solutions. Granted these kits are not cheap, but you are buying them to make "accurate" measurements regarding the chemistry of your aquaria. Why contaminate these reagents? It is better to waste that 0.2cc's of reagent than contaminate the remaining 45 tests in the reagent bottle.
8) Most important...Read the directions thoroughly before performing any test. The picture cards that come with the tests are nice, and are a great reference once you are familiar with the test.
I hope this has been some help to you. I've just helped a friend who was having problems with his tank and testing. He complained his test kits, the same one's I use were bad. We compared results only to find out his technique needed some improvement. He's now confident and consistent with his testing
1) Preparation of sample vials and measuring equipment (syringes, beakers, graduate cylinders, etc.). Rinsing this equipment with RODI/Distilled water will help get rid of any latent chemicals, deposits and debris from your previous testing and storage of that equipment. Follow this by a good rinsing with your sample water. Don't dry the equipment, just use them with the sample that you want tested.
2) Measurement of samples, reagents, etc with syringes. Remember to do this the same way each time. In syringes, there will be an air bubble. This is the air in the tip of the syringe. You can do one of two things. Fill the syringe so that the bottom of the bubble is at the desired mark on the syringe, or fill it where the plunger is at the desired mark. I recommend the latter, because when the bottom of the plunger hits the bottom of the syringe barrel, the air bubble pushes out the last little amount in the syringe, giving you the "exact amount" of the solution you needed.
3) Measurement of samples, etc with graduated cylinders, pipettes, etc. A meniscus (concave surface) forms when measuring solutions. This is caused when the liquid adheres to the wall of measuring device. The bottom of this curved surface is the true measurements. (However, substances that do not adhere to the wall, such as mercury (not used much) will form a convex surface. You read the top of the surface in this case. Very, Very Rare).
4) Measurement with droppers and dropper bottles. The bottle/dropper is held "perfectly" vertical to form the drop. The drop falls off the tip and is not shaken or tapped off or even dipped into the test vial.
5) Swirling your solutions, rather than shaking them. Shaking can introduce air into the solution, which may alter the results. An old chemist's trick is to flick the test vial with your middle finger of your free hand. Make sure you mix the solutions for the full amount of time indicated in the instructions.
6) Cleaning your equipment. A thorough wash in warm, soapy water should be followed by a good rinse in regular water. Follow this with a thorough rinse in RODI/Distilled water. I don't recommend drying your equipment with paper towels, cloth towels, etc. These leave lint and other contaminants. Ideally, get some acetone from your hardware store and rinse the equipment out. Acetone dries very quickly and leaves no residue. If your equipment has caps, you can put them on, but don't close them tightly.
7) Care of your Reagents/Chemicals. Some kits say that you can put the unused portions of titrating agents back into their respective containers. IMO, this is the quickest way to contaminate those solutions. Granted these kits are not cheap, but you are buying them to make "accurate" measurements regarding the chemistry of your aquaria. Why contaminate these reagents? It is better to waste that 0.2cc's of reagent than contaminate the remaining 45 tests in the reagent bottle.
8) Most important...Read the directions thoroughly before performing any test. The picture cards that come with the tests are nice, and are a great reference once you are familiar with the test.
I hope this has been some help to you. I've just helped a friend who was having problems with his tank and testing. He complained his test kits, the same one's I use were bad. We compared results only to find out his technique needed some improvement. He's now confident and consistent with his testing
