Robyn, I have seen you mention a bioball several times and am wondering what is a bioball? Also, my pond was 1 year old in March and I have never checked the PH. Should I be doing that? I have not lost any fish except to a snake and possibly a Bullfrog (i saw the photo of the frog and goldfish on your newletter). My biggest goldfish just vanished....no signs of him.

Here's an image of what my bioballs look like:
http://arasto.persiangig.com/discuss/bioball2_th.jpg
If you look up "bioballs" on a search engine, you'll find lots of information.

You should check the pH.

Sorry your goldfish vanished.

My understanding is the bioball is designed to provide a lot of surface area for good bacteria to grow.

I need your advice...why is it necessary to check the ph, especially when it "seems" like everything is ok in the pond? What are the advantages of doing so, and what is it that the ph tells you? I just didn't know that it is something that you have to do.

ph tells you how acidic or basic your water is on a scale from 1-14 ... 7 being neutral... certain fish thrive in certain ph ranges. some like more basic, some like slightly acidic and others like relatively neutral. the higher the number, the more basic and the lower the number the more acidic.

for instance:

0-2 range would be hydrochloric acid, stomach acids, etc
~3 would be vinegar and some hair conditioner
4-5 = hydrogen peroxide
7 = distilled water
7.5 or so = blood
12 = ammonia

Is testing the ph a HAVE to thing? And how do you test for ph?

You want to test your pH intially to know what kind of water you have, if it needs adjustments, and what kinds of fish will do okay in that kind of water. As the pond ages, the pH changes (usually up) and fluctuates depending on the time of the day, being most acidic at dawn. This is because plants take up carbon dioxide during the day but release it at night. When they release it, it's like adding carbonic acid to the water which is basically carbonated water. If a pond has too many plants and/or low buffering capacity (as determined by the hardness and alkalinity which you should also test), the pH can crash (drop low) in the morning and result in dead fish. It doesn't help that dawn is when the oxygen levels in the pond are also the lowest since plants and fish both use oxygen at night. This is why it's even more important to aerate a pond at night than during the day.

Once you know your initial pH, it's a good idea to test weekly for the first season (record time of day too). Then, you know what's normal. After that, test at least twice a year and certainly when you think there might be a problem. I only test the pH a few times a year.

Nice explanation and examples, JarrodRossi. Thanks.