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🐟 Master your aquarium’s health with precision and confidence!
The API 800 Test Freshwater Aquarium Water Master Test Kit is a professional-grade liquid testing system designed exclusively for freshwater tanks. It accurately measures five critical water parameters—pH, High Range pH, Ammonia, Nitrite, and Nitrate—using seven sealed reagent bottles and four durable glass test tubes. This kit offers superior reliability over test strips, providing clear, repeatable results that help prevent fish loss and maintain optimal aquatic health. Ideal for weekly monitoring and troubleshooting, it’s the go-to choice for serious aquarium enthusiasts and professionals alike.


















| ASIN | B000255NCI |
| Batteries Included | No |
| Batteries required | No |
| Best Sellers Rank | 1,226 in Pet Supplies ( See Top 100 in Pet Supplies ) 2 in Aquarium Test Kits |
| Compatible Devices | Designed for use in freshwater aquariums only |
| Customer Reviews | 4.8 4.8 out of 5 stars (30,291) |
| Date First Available | 25 Nov. 2009 |
| Delivery information | We cannot deliver certain products outside mainland UK ( Details ). We will only be able to confirm if this product can be delivered to your chosen address when you enter your delivery address at checkout. |
| Item Weight | 522 g |
| Item model number | 34 |
| Number of Items | 1 |
| Pet Type | Fish |
| Product Dimensions | 23.2 x 8.9 x 11.8 cm; 521.63 g |
| Quantity | 1 |
| Size | One Size |
| Special features | Accurately monitors five most vital water parameters levels in freshwater aquariums: pH, High Range PH, Ammonia, Nitrite and Nitrate |
| Volume | 250 Millilitres |
D**N
Very accurate so totally reliable.
I moved away from test strips and bought the API 800 Test Freshwater Master Kit. One of the best decisions I have made for my aquarium. Test strips may look convenient but once the container is opened and the strips are exposed to air the clock is ticking. Moisture and oxygen start degrading the reagents immediately. After about 30 days the accuracy drops off badly. At that point the readings are questionable and you may as well consider them unreliable. For something as important as water quality, that simply is not good enough. The API Freshwater Master Kit solves that problem completely. The reagents are stored in sealed bottles so they remain stable and accurate for a long time. Using it is straightforward. Fill the test tube with tank water to the line, add the correct number of drops from the bottle, cap the tube and shake. For nitrate there is a second bottle and a longer shake but it is still very simple. Wait the specified time, then compare the colour against the chart. That is it. What you get in return is far more reliable information. The colour changes are clearer and the scale is more precise than strips. You can properly track ammonia, nitrite, nitrate and pH rather than relying on vague strip colours that can be difficult to read. Each kit also lasts a very long time because you get a large number of tests from the bottles. It ends up being far better value than constantly replacing strips that degrade quickly. If you want accurate, repeatable readings and a clear picture of what is happening in your tank water, this kit is excellent. Simple to use, dependable and well worth the money. Highly recommended for any serious fish keeper. 🐟
P**L
Axolotl Tank Tester
I keep axolotls, and as any axolotl keeper knows, they are very sensitive to water conditions (although many fishkeepers will know the same about some species of their fish). The point of the API Freshwater Master Liquid Test kit is to enable you to test each parameter safely and quickly to troubleshoot any problems in the aquarium. As a keeper it is also a very good idea to test weekly as part of tank upkeep, after a water change, to ensure an ongoing healthy aquarium. What does it do? Each liquid test kit tests for essential parameters such as ammonia, which is a killer, nitrite, which is less deadly but still lethal, and nitrate, which can cause problems if too high. It also enables you to test for elevated PHs. The kit is vital for testing for 'spikes' in these chemicals. It also enables you to assess the bacteria culture in your tank - if ammonia is converting to nitrate (i.e low or no ammonia, low or no nitrite and under 40ppm nitrate) you have a cycled, healthy tank. What do you get for the money? A computer calibrated test sheet, with colours that show the result of each test - place the completed test sample in its test tube over each colour. Whichever colour is hardest to see through the liquid is the closest match. It also contains a card which tells you which API products to use if you ever encounter problems (although personally I would enquire on hobby boards as they offer good advice). It also contains a booklet detailing how to do each test, with tables at the back to record your own results for a few weeks or so. It comes with four test tubes, which don't shatter when they break despite being made of glass - having four enables you to do ammonia, nitrite, nitrate and PH tests all in one lot). It also comes with reagents to test for AMMONIA, NITRITE, NITRATE, PH AND HIGH RANGE PH. You may need to use more of the nitrate and ammonia tests, as these use two different bottles each to complete each test, and quite a few more drops from each bottle than the other tests. You can buy these separately, but at £18 for a full set, and £6 separately, you may as well buy the full kit. Are the tests difficult? Not at all! PH and High Range Kits require only five drops of liquid with 5ml of tank water (clearly marked with a line so easy to fill) and to be left for barely a few seconds. The most complicated test is Nitrate, as it requires two bottles and over a minute and a half of shaking, but clear instructions are included, step-by-step, in English, French and Spanish. They are not difficult at all and over time can be done from memory. How long do they take? For the PH Tests, a few seconds. Each of the others requires five minutes to develop. The Nitrate takes as long as 6 and a half minutes because of the shaking process. Any tips? When testing, always leave bottles on a flat surface to avoid them rolling off. Also, with the Nitrate test, add Bottle No 1 to the test sample, shake to mix, then place on a flat surface. Remove the plastic lid and wipe it out before replacing - I find this prevents a lot of leaking when you do Bottle No 2's test. Do you recommend them? Definetely! I knew very little about tanks but the kit enables me to keep on top of their upkeep easily and is invaluable for ensuring my axolotls aren't sick because of parameters. They are easy to use and last ages - my last kit was bought in April (6 months ago) and I am only ordering a new one because I broke two test tubes and am running out of the Nitrate tests. They are much more reliable than the strip tests - the API kit is also the most recommended kit on Caudata.org, one of the best amphibian sites on the net, and also one of the cheapest. The only downsides are that the nitrate runs out quicker than the others, and that I have managed to break two test tubes by moderate falls, but buying a new kit remedies that, and as I said before, the glass does not shatter - the bottom simply falls off it it meets a hard impact. The colour charts can be difficult to read, particularly Nitrate, which has around three shades of orange or red that can be hard to distinguish - ask for a second opinion and always do them in good light to remedy this (if desperate ask on a forum, posting pictures), but generally Nitrate is the only one you may struggle with. Overall, one of the best purchases possible for your aquarium.
M**R
Best kit for overall price and good accuracy. Few caveats but still highly recommend.
The only freshwater master kit i will use. Test strips i never used due to there poor accuracy. There are some other brands like Seachem for example that do great water testing products but much more expensive to. If you want good accuracy for a reasonable price that will last a reasonably long time then overall value and quality is definitely given to the API Freshwater Master Kit. You can perform the following tests with this kit: - pH - low range - pH - high range - Ammonia - Nitrite - Nitrate Comes with easy to follow instructions and colour chart. The most annoying are the test tubes, i always end up breaking them and having to buy spares, i also hate they are push caps and not screw on as you have to keep your thumb on top of the cap when shaking as it tends to leak out otherwise, i also wish the case layout was better as well as it's a bit annoying and fiddly specially the position of the test tubes. I also purchased the API liquid Kh and Gh kit to make it a true master test kit. I think they should be included as standard as this is called a master test kit after all. Make sure you shake the plastic liquid bottles very well before using, i shake longer than the instructions state to ensure it's mixed well, specially the nitrate bottle as it's very thick formula and prone to giving inaccurate readings simply because the bottle was not shaked enough before using, so take note shake and shake again. I recommend this kit for any fish keeper whether you are newbie or advanced user, this kit is suitable for most peoples needs. I tend to only test frequently when cycling a tank and for approx 6 months after cycling complete whilst beneficial bacteria still colonizes in the filter, i don't test often from then on as i find observing the tank and fish can give you good indicators of problems, but nonetheless still a great kit to have to hand for as and when needed. Check readings in natural daylight if possible as can sometimes be hard to judge colour of tested water against colour chart. Best kit for overall price accuracy and price. Highly recommend. Tips: - Check expiry date is well in to the future on case when it arrives as they last ages. - I find placing the colour chart up against a window with natural daylight (but not direct sunlight) and then placing the tube by the side of the test i'm testing enables me personally to take a better reading. - Another way some people find easier is to place the colour chart down flat on a surface in a room with natural daylight, then remove cap from test tube and then place the testing tube on top of the colour chart and test they are testing for, then look straight down the test tube and compare colour. - Some people complain of the colour in the test tube changing over time and not sure which reading was correct, this will happen hence why it's important to follow instructions. If for example you are told to compare the test tube with colour chart after 5 minutes, then ensure you compare after 5 minutes and not for example 10 minutes, as overtime the colour will continue to change and people then get confused which is the correct reading. - Shake the Nitrate bottles as it's very thick formula and prone to giving people false readings, read the instructions very carefully, a number of people do the Nitrate test wrong and get inconsistent inaccurate readings. You must shake this bottle excessively. I always shake the bottles longer than the instructions state to ensure they've been shaken enough, if you don't shake them enough you can end up with inaccurate false readings.
S**B
Good 👍 Work's Well
L**Y
love my testing kit has always help when i ran into problems
C**A
Excellent Quality. Accurate test result. I recommend this product. Delivery recieved early
B**Y
There is a reason why this test kit is considered the best amongst aquarists and fishkeepers. It is more on the pricey side and there are definitely more cost effectivr kits in the market. However, it very simple to use and the instructions are easy to follow. Highly recommend this kit for individuals starting out in the hobby as testing the water is essential for keeping your fish alive.
C**Y
Good product
Trustpilot
1 month ago
4 days ago