8 Year Old Reef tank Failing! What Do I do?

[Brew12]

@Brew12

Thanks for the call out!

I suspect you have a few things going on that are giving you this reading. First, I'm guessing your RODI container isn't completely non-conductive anymore. If you take your meter and do a resistance reading with both probes in the water you should get the meter to not be able to get a measurement. I think you will see some measurement, and maybe even in the kiloohm range or lower.

The reason you are seeing voltage go up as the container moves toward the tank has a few possible causes. You could be moving it closer to power cords with current running through them. It could be picking up magnetic fields from a pump in the sump area. Or, if you use T5's or metal halides, it could be getting some voltage from the emitted photons.

If you want to see just how much induced voltage you can get in water you can try this. Take the longest extension cord you have and coil it around bucket of salt water. Run something like a space heater, coffee maker, or microwave oven off of the extension cord. While the load is running, take a measurement. You should easily get over 50V.

 

[blue-thumb]

I'll try not to get too zen. Tanks have moods. The less mature a tank is ... the moodier it is. Stability is the key. Anything that messes with the microfauna in your tank (i.e bacterial populations) will upset your tank. It's frustrating because you can't see it. Fish and corals are depended upon the bacterial to maintain good water quality. The more you fight with your tank the less stable it becomes. It becomes harder it becomes to determine the source of the problem. Change one variable at a time. Wait to see what changes. Nothing good happens quickly. The vast majority of problems I've had I created by making to many changes.

I will say that I hate sand in coral tanks. Corals love flow. Lots of it. Fine sand makes it hard to turn up the juice. Second, overtime uneaten food and detritis begins to accumulate in the sand. If not cleaned frequently then it becomes a great anaerobic environment. Place it in a cup and leave it for a day. The rotten egg smell is hydrogen sulfide. Highly toxic to fish and corals. As your sand bed shifts hydrogen sulfide will be released in the water. it's release is intermittent. You probably wouldn't see it on an ICP test. Having sand in a tanks isn't worth the potential benefit (largely aesthetic). It increases tank maintenance time. Removing sand from my tank was the happiest of my reefing life.

 

[Uncle99]

Do you have a volt meter to test voltage?

The worst thing one can do to fix a reef tank is try too many fixes too fast, that'll just stress everything out (I do see you've been trying over a few yrs)

+1....yup, that’s a lot of changes.
You were told water chemistry is great, but you post no results of the test.
IMO, poor water chemistry, instability, and/or multiple changes lead to many of our problems.
I have found that the best solution to an unknown problem is to firstly, rule out the obvious.