Water conditions often point to a root cause for an issue your aquarium may be experiencing. We all love our fish and our aquariums are very large investments of our time and our cashflow. Taking care of them properly and diagnosing problems quickly and correctly will make your experience much more fulfilling and enjoyable.
So is testing your water important? Well, yes, absolutely! Water conditions help to give a map to possible health issues as well as a myriad of other things. For the general aquariast the most important things to test for are Ammonia, Nitrite, Nitrate, and PH. Other more advanced aquariasts may choose to test other things and they will be addressed later in this article. Often times people set up an aquarium and do not allow it to cycle completely or are completely unaware that they may need to cycle their aquarium. During this phase Ammonia and Nitrite levels will rise dramatically and fluctuate as bacteria colonies form to assist in the Nitrate Cycle. During this time it is very important for you to test your water to avoid possible disaster and death of your aquariums inhabitants.
For people with established aquariums it is still important to do regular testing. This is preventative maintenance, no different than getting a check-up yourself. You may feel okay but issues may be developing. Rises in ammonia or nitrites might signal mini cycling is occuring and may stress or even kill some fish. It's always a good thing to know how your tank is doing because you can't see it .. so test for it.
Some of the more advanced tests may give more insight into issues you may have. Algea blooms may be a sign of high phosphorus levels. People who keep special types of fish or planted aquariums may want to test their hardness. There are tests for these but for the average aquariast they are not really needed. These tests are expensive and should be used if needed but again, for the average aquariast they are above and beyond.. so save your money unless these tests mean something to you... and in that case you probably know why you need to be testing in the first place.
Help us Help You!
If you want to ask for advice or help from members of this sight it will greatly help them and you if you know these few things:
PH, Ammonia, Nitrite, Nitrate, Water Temperature, (optional)Hardness, (optional)phosphates and other hard minerals, .. The type of filtration you have, How recent your last maintenance was performed, Have you added anything recently? Also be sure to list ALL of your symptoms..
Please do not ask for help when the only thing you can offer is, "One day my fish were fine, the next day they were all dead."
With proper information we can help you enjoy your aquarium and help you keep your fish and other tank mates healthy.
This was taken directly from:
http://www.monsterfishkeepers.com/forums/showthread.php?t=113815