thats cuz you don't have any leakage. Grounding probes don't solve the problem they hid it, a GFI is realy all you require and if it trips you have a problem.

I split my equipment up between 4 GFI's my self I ran two heaters two MH lights and two actinic ect all set up on different GFIs. this solves the problem if one trips you don't lose everything.

Steve

Though they say a GFCI will trip fast enough to protect you still rather it trips on a ground probe than using me as the path to ground.

Thats the purpose of the GFCI it trips before the electricity uses you as a path to ground.

May be 1/2 a cycle but the comparator cct needs to see the imbalance, that's through me without a ground probe

If the fault is in the light and the ground probe is in the tank, then it is still through you.
On a side note a GFCI must trip at 0.006 Amps so I don't think 0.0059 Amps for a time of 0.0083 will be of any concern.
Plus the ground probe is a lower imperdance path to ground than any other possible path for the current, and lower impedance means higher current.

Here are two links to some additional reading material on the subject. Seems from a bona fide source. Personally I split my system load between two GFCI devices and do not use a grounding probe. For added redundancy, each GFCI is on a different circuit breaker. The only buzz I have ever experienced is while brushing my clip on T5HO reflectors with my arm while my hand was in the water. I assume the T5 lamps induced voltage in the reflectors and I completed the path to the water through my arm. I have since individually grounded each of my reflectors and the problem is solved. This was not sufficient to trip a GFCI device, so I also assume the buzz was harmless, below the danger threshold of a healthy individual. Someone with a pacemaker might have had a problem. If I recall correctly, before grounding the reflectors, I read about 30 volts AC between the reflectors and the water. So that potential was always there, but had no place to go until my arm completed the path to the water. If you install a grounding probe in your system, the same situation may arise, with a voltage potential with no path, until a grounding probe or you provides it.

http://angel-strike.com/aquarium/GFI...alDetails.html

http://angel-strike.com/aquarium/GroundingProbes.html

well here is my story: I got electrocuted when i was mixing my water the other days. All my tank equipments are split among 2 GFCIs, but for some lazy reason, i hooked my powerhead to a normal outlet and some water leaked into the outlet that i did not see. I got a huge shock but was ok. Maybe my body get used to these because i got shocked so many times (more or less 10 times) when i was a kid and with 220V voltage instead of 110V. But it is something i don't want to experience

Where does one purchase a GFI probe? and is one better then the other.

home depot sells singles, twin and three packs. there all about the same, I buy the fancy ones with the light that tells you if it is hooked up and working right.

Steve

also given that the GFI must trip at 0.006amp, it shows that is it 10 times lower than what is concidered deadly to a healthy person. 0.06 amps will kill a healthy person if it travels through the heart. this is why they have GFIs, they will trip befor the amprage is anywhere near what is needed to be deadly. a person with a weak heart will requite over 0.03 amps.

Remember these numbers are only if the current passes through your heart. if you are wiping the glass in the tank and brush your shoulder against the lights and get a zap, it is highly unlikly that it would pass through your heart as the quickest path to ground is in your shoulder and out your hand to the water. now if you were cleaning with the left hand and grab the lights with your right and if the amprage is large enough you had a grounding probe, you would still probably be dead as the probe just insures that your hand is in a ground path. so in a way you have more of a chance of getting shocked by a exteranal fixture if you have a ground probe.

my opinion is to install GFIs and through the grounding probe in the garbage.

one thing to note, is GFI outlets still need to be tested ocasionaly time to time. make this a part of your normal maintenance routeens.

Steve