What's sharing your water? Find out whether your water contains bacteria.

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What's sharing your water?

We usually can't see bacteria in water but they are the first thing we should be concerned about in our drinking water. If your water comes from any untreated source like a dam, creek spring or even from a rainwater tank you should test for bacteria.

Which bacteria? Now finding out what types of bacteria you have in your water and how many is relatively easy. There are easy to use kits you can buy and take home to do the testing right where it counts. The advantage is that you choose where you test and how often. Samples are fresher and you get results faster. The other reason is that you can take a more active role in finding out about your own water. Here's a quick rundown on the types of bacteria which can be tested for in water using the kits we supply. (Note: Aeromonas and Salmonella tests not currently available).

E coli. They indicate fecal contamination from warm blooded animals. They are mostly not dangerous in themselves but are used as an indicator of contamination.

Coliforms. Mostly friendly bacteria common in water and soil. Again if you've got lots in your water you probably need to disinfect it.

Aerobic bacteria. Sometimes called Total Count. Again a good indicator of total loading.

Aeromonas spp. Some of this type of bacteria are pathogens so if you get Aeromonas bacteria in your sample disinfect your water. It's now thought that Aeromonas are just as good an indicator of water quality as E coli. (Membrane filter kits only). (Not currently available).

Salmonella spp. Now you really don't want these in your water. (Membrane filter kits only - check with us first to see if the special MF kit that includes Salmonella is available). (Not currently available).

Which kits? We use and supply Micrology Laboratories kits from the USA. They are easy to use and provide better information than any other kits we've seen. If you want to test your own water the range of test kits is at Test kits. If you prefer to have us test for bacteria see the section on water tests at Bacteria water quality tests.

Test before drinking. If you want to drink your water then use a Coliscan kit or Home drinking water kit. Find these under Test kits on this site. These are best for getting a good handle on which bacteria you've got and how many. So they are best for source water eg from a spring or dam etc. The Total bacteria test kit is also worthwhile because it will tell you the total bacteria load and this will indicate if you have a contamination or pollution problem.

Check the section on bacteria and do it youself bacteria tests at bacteria.

If you absolutely positively must know... choose Membrane filtration kits. There are two types of tests. In the 'plate' method you add from 1 to 5 ml of sample to a bottle of growth media, mix it then pour it into a special growth dish. After a short incubation time you count the colonies. So you are trying to get an indication of bacteria from just a very small sub sample (1 to 5 mls). This is OK for the common bacteria or if your water is untreated. But if you are testing water ready for drinking or you want to know more positively that there are no E coli in the water (an indicator species) then choose the membrane filtration method. With this method you filter 100 or 150 mls. It's much more 'statistically' significant to take 100 mls and capture all the bacteria in that sample.

All MF tests were once done in the lab but now they can be purchased as kits.
New
. Membrane filtration kits are now available - see tests at ECA Check MF kits.(Note: Not currently available).

Which test? There are 5 test kits available on this website. Each has its good points.

1. Coliscan drinking water kit. For testing drinking water. Tells you how many E coli and general coliforms you have. The kit has 3 individual tests. For full details on the tests see Bacteria test kits.

2. Home water quality test kit. A good combination of 5 tests, E coli tests (3) and total bacteria (2). It will tell you how many E coli, general coliforms and total bacteria you've got. Like to see how the kits work? Just click here for a step by step guide with pictures Easygel step by step.

Your water could end up like this if you don't monitor bacteria levels. This is from a sample of tank water tested with the Total count bacteria test kit. Levels in this sample were 450000 CFU's per 100 ml which is very high.

3. Coliform bacteria test kit. This kit contains 3 tests for general coliforms. Because coliforms are a good indicator of overall quality this test is a good screening test.

4. Total count bacteria test kit. Contains 3 individual plate tests which will show total bacteria colonies (CFU's) in your water. Use this test in combination with the Coliform test and the Coliscan test to get a good overall picture of water quality.

5. ECA Check Membrane Filter kit. In this test you filter a known amount of water through a very fine filter. The ECA Check method distinguishes and measures E coli, coliforms, Aeromonas spp (an advanced version also detects Salmonella spp.) Check out this easy step by step guide - in pictures to see how the ECA Check kits work ECA Check step by step. (Note: Not currently available).

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