Why You Should Avoid Low Quality Test Kits

Welcome to Simple Reefs. We are a brand new website designed to take the stress and expense out of starting your very own marine aquarium. We’ve been talking about marine aquarium test kits this week. Today, we are going to be talking about why you should avoid low quality test kits and we will also give you a few tips on how to recognise them.

This article has been updated to split it up a little bit and make it a bit more readable. I realised that I had somehow pushed out a 3,000 word article about test kits. That’s probably a bit too much so I decided to break it up into bite sized chunks. Well, if 2000 words is bitesize, that is.. You can find the section on why high quality test kits are important by clicking this link right here.

Don’t Try to Save Money on Safety!

We started off this week by discussing the importance of test kits to a marine aquarium before giving you a little help on picking which test kits to buy. That’s all well and good but this is where the subject gets a little bit complicated. Particularly when the website that you have created is designed to help people save money.

We’ve already talked about how much money test kits can save you in the long run. They are the uncrowned champions of your marine aquarium tool-kit, providing you with an early warning when things go wrong. Early detection of potential problems can help you prevent said problems escalating. This can save you a lot of time, effort, and financial burden when it comes to dealing with issues.

The thing is, not all test kits are created equal. This is just a sad fact of life. Companies aren’t afraid to sell products that aren’t up to scratch. When you consider how delicate your miniature eco-system is, and how expensive it is. It really isn’t worth trying to save a few quid by opting for a lesser brand.

Of all the different ways in which you can cut costs on your saltwater journey, safety is not the best place to do it. With this in mind, finding test kits that are reliable and accurate is of absolute paramount importance. Even if said test kits cost a few extra pounds. Believe it or not, spending more now can safe you money in the long run and I will tell you why shortly.

The Woes of a Low Quality Test Kit

You may be wondering “what’s the big deal? At least I am testing my water” and to some degree, you are right. Some testing is better than no testing… most of the time, anyway. The problems come when your test kit is woefully inaccurate. Let’s take a look at a few ways a low quality test kit can go wrong.

• Difficult to Read: Colours that are barely different, long development times, short windows to check the colour. All of these things are big problems with low quality test kits.
• Difficult to Perform Tests: Take a sample of water, add ten drops of a certain fluid that barely wants to come out of the bottle, perform five backflips while reciting the words to Jeff Buckley’s version of Halleluiah, add ten drops of another liquid, touch your toes and say 10 Hail Marys. Some test kits have instructions that are either horribly unclear or ridiculously convoluted making testing a massive pain.
• Inaccurate Results: This is something you might only spot when you suspect that the reading is incorrect. Some low quality test kits are always inaccurate, no matter how carefully you perform the test. Comparing results to more accurate sources like digital checkers and your local fish shop will reveal big problems.
• Variable Results: Results seemingly changing wildly between tests with no logic and no sense is very common with low quality tests. They are often extremely variable and very unreliable.
• Imprecise: Many low quality test kits are very imprecise. The result will have to round up to whole numbers or fractions rather than actual accurate and precise numbers. This can make adjusting your aquarium dosing very difficult.
• False Positives: Certain low quality test kits will give false positive test results. Look at the image below, this was an API ammonia test taken on a very mature tank that I knew had 0PPM Ammonia in it. It shows well over 0PPM. This is extremely common.

Certain test kits can be difficult to read, variable in results, difficult to actually use, and, ultimately, inaccurate. Some will even arrive to your doorstep already expired. I have used test kits, in the past, that will produce a different result every time the test is repeated. Even with the instructions being followed down to the letter.

I have also used test kits that I know will give me positive results despite every other test kit I own giving me negative results. This is particularly problematic with Ammonia and Nitrite test kits. Especially where cycling a new marine aquarium is concerned (check out our article on cycling a new marine aquarium).

The Problems a Low Quality Test Kit Can Cause

The problem with poor quality test kits is that they can do more harm than good. If a test kit is so inaccurate that it displays a significantly incorrect result, it could prompt drastic, and dangerous, action from the owner.

Say, for example, a test kit reports that you have high levels of nitrates when, in reality, your nitrates are fairly low. This could prompt you to perform numerous large water changes that upset the stability of your tank. This could lead to the development of things like dinoflagellates which thrive in nutrient deficient environments.

What if an inaccurate calcium test kit gives you a wrong reading and you adjust accordingly? Your calcium levels could go through the roof which might upset the Alkalinity and pH levels of your water and cause all sorts of problems. A bad test kit is, in some cases, worse than no test kit at all.

How to Identify a Low Quality Test Kit

You may be wondering how to identify a low quality test kit. Well, unfortunately it isn’t quite as simple as you might think. Especially in a world absolutely filled with fake reviews and misinformation. Test kits that I absolutely concretely know to be inaccurate are often well reviewed and recommended.

The problems come when the people performing the tests don’t actually realise that the results are inaccurate. They have limited experience and can’t apply acquired knowledge to what they are seeing to deem it unreliable. They certainly don’t have the ability to cross check the result against a more accurate test kit.

Generally speaking, if the price seems “too good to be true” it probably is. Test kits that come in one “Master Kit” for a very low price should be looked on with caution. Test kits that are advertised as being for freshwater, primarily, should be avoided.

Take a look at reviews and user experiences. Focus on the more critical, yet balanced, comments and look for people saying that the tests are difficult to perform, variable, or difficult to read. You do have to temper your expectations, a little. Many test kits are difficult to read by their very nature but when it is combined with other issues, it’s a red flag.

Stay away from kits with short expiry dates. If the kit only has six months, or a year, left, give it a wide berth. If the dates on the reagents don’t match, send the kit back. If the kit is in test strip form, just avoid it. They are difficult to read and rather inaccurate.

Low Quality Test Kits to Stay Away From

As I mentioned earlier, test strips are always to be avoided. The only type I will use are the type that detect chlorine. They are frequently inaccurate and the results almost never match up with those of a reliable kit.

I think that you should probably avoid NT Labs Marine Lab Reef Multi-Test Kit. Their standard kit for Ammonia, Nitrite, Nitrate, and pH is fine, though hard to read. Their advanced kit for Phosphate, Magnesium, Calcium and Alkalinity is painfully inaccurate. If you enjoy getting a different reading every time you test then you will love it.

I would seriously consider avoiding JBL’s Marin Combiset. I haven’t used it myself but I have heard horrible things about how wildly inaccurate these tests are. Sometimes out by 200% which is an extremely worrying amount. This is a prime example of where no test kit would be better than a low quality test kit.

I don’t want to pile on API’s test kits because they have a bit of a bad reputation but I have, personally, found them to be very inaccurate. Perhaps this should be expected with the low price of the master test kit but it’s still a problem. I am actually going to relate a personal experience here with some proof as these kits often receive good reviews from people who don’t know better.

A Personal Experience with Low Quality Test Kits

I actually started with an API Salt Water Master Test Kit. The price seemed great and I appreciated having full coverage of all the major test markers. I started to notice a problem with these test results very early on. As I gained more experience, I could confirm that they were, frequently, very inaccurate.

I have always followed instructions down to the letter with all the test kits that I use. I meticulously clean my test vials and they never have streaks or residue. Despite this, results that are in line with my Hanna testers, fish shop tests, and more well regarded test kits, are hard to come by.

If you check out the image above you will see the API test I took of water from an aquarium that I knew to have 13PPM nitrates. I received this number from a Hanna test kit and had it confirmed by my LFS. As you can see, the API test is showing something in the region of 40PPM+. Your screen may make it look a little different and I couldn’t capture it in a way that made it clear in a photo. In person, however, this was very obviously 40PPM.

This kit was not expired and had well over a year left on the reagents. The vials were cleaned meticulously and rinsed with reverse osmosis water. The test was performed exactly as suggested and thoroughly mixed. Despite this, I knew this result would be way off before I even took the test.

Now let’s take a look at the Salifert nitrate test equivalent. Again, let me emphasise, I know the nitrate levels in this tank, I have had them confirmed via digital checkers that minimise error and by a LFS – they are 13 PPM. The Salifert test result below appears to indicate a pink that is slightly darker than that of the 10PPM rating. It looks a little off due to the photo being taken on a phone and the shadow I am casting but the hash colour (checked in a graphic editor) is slightly darker.

That slightly darker pink colour indicates that the water is slightly over 10PPM which is very accurate. How do two different test kits, performed so that they finish at the exact same time, using a sample of water taken at the same time from the same tank, have such wildly different results?

Some people swear by API test kits and blame user error but if the tests are this sensitive to user induced variables then they are not useful anyway. User induced variables are always going to be a factor and shouldn’t cause hugely inaccurate results. It doesn’t happen with Salifert, it doesn’t happen with Red Sea, it doesn’t happen with Hanna. It only happens with low quality kits like API.

In Short

Low quality test kits may seem tempting due to their affordable price. The truth is, however, the lack of accuracy and precision, difficulty of reading, and their inconsistency may make them a very false economy indeed. Low quality test kits can have you chasing your tail trying to find the right numbers. They can make you overreact to certain situations and overreact to others. Spend a little extra on a high quality test kit and you may just save a lot of money in the long run. Thanks for spending your time at Simple Reefs.