Quote:
Originally Posted by
JasPR 
right, check your oxygen reading before and after feeding and check your pH in the early morning and early evening.
The point of an orp reading is to get a glimpse of the worst ORP reading in the pond and not the best reading for bragging rights. In that regard, you WANT to get a reading when your oxygen is at it's lowest and your pH is at it's highest and lowest. You should NOT assume that pH is always the same but if , in your testing/investigating, you do see wild swings in your pH this is another conversation and maybe more important than your ORP reading.
In all modesty, I brought ORP to the ponding hobby here on the net, some 13 years ago now. And I now have mixed feelings about doing it as it has become THE most misunderstood test in the koi hobby.
I will mention this again - an ORP reading is both a relative reading and a trend reading. It is NOT a reading like temperature. ammonia presence or even pH. The number can not be interpreted by the readngs from others and only general statements can be made about it. And although there are definite BAD readings and VERY GOOD readings, there are just as many illusionary readings. Take ORP readings with a grain of salt until you have logged a trend line for your pond against a backdrop of oxygen , temperature and pH.
a word to the wise--- JR