Considering restarting 75 gallon tank

[JohnD10557]

I have kept a thriving 75 gallon reef tank for almost 10 years. I had live rock, fish, anemone, shrimp, some corals, hermit crabs and other assorted cleaners. Then, about a year ago, I started getting pretty bad algae. About four months ago, I was in an accident, broke several bones and was laid up, unable to maintain the tank and all my livestock died with the exception of a cleaner shrimp and several hermit crabs. Now, I've re-stabilized it, however, I can't keep damsels alive for more than 12 hours and soft invertebrates(snails, sea hares,etc) literally "crawl out of their shells" and die in 5 minutes or less. At the same time, I still have the cleaner shrimp and several hermit crabs that seem to thrive, but that's all. I've tested for ammonia, nitrates, nitrites, Ph, salinity, and copper, and all those tests(both at home and several stores) have come back fine. I've been trying to re-introduce livestock for close to 2 months now with no success. Considering restarting by either boiling(sterilizing) my substrate and rock or replacing, but if I have to spend another $600 plus to replace all my substrate and rock, I may just give it up.
As long as the problem isn't chemical(as in "toxic metal contamination") would sterilizing get me a good restart?
Any other ideas out there?

Thanks

 

[Ziggy953]

Test your water again and post the results. Something is going on and it sounds to me like the tank needs to cycle again.

What kind of filtration are you using on the system?

 

[abrahamavelar]

did u add any nti chlorine thingy and how cold is the water

 

[JohnD10557]

Here are some recent test results(as of this morning).

Salinity - 1.021
ammonia - 0 ppm
Ph - 8.3
Nitrate - 0 ppm
Nitrite - 0 ppm
Copper - 0.05 ppm(lowest on scale)
Temp - 78 degrees F
I use 2 large off the back filter systems(Penguin 330 and a Tetra) as well as protein skimmer and 220 watts power compact 10K and actinic.

Up till now, all water was RO filtered and kept in a 50 gallon resevoir holding tank.


JohnD

 

[abrahamavelar]

ill add alittle bit more sand i usually keep mine at 1.023 do you have enough water movement for it to create oxygen?

 

[JohnD10557]

Here's the weird thing. I have several sources of water current in the tank(power heads), so I think oxygen's good, but when I try to introduce a fish, like a damsel, it lasts for about 8 hours, then dies. When I introduce a soft invertebrate, like a snail(turbo grazer) it literally crawls out of it's shell and dies in about 3-5 minutes! A number of months ago, I tested electrical current, found about 100 volts of AC running through the tank, installed an electrical ground, and now the voltage is zero. Every week or two I try to re-introduce a damsel or snail, but no success, and still my cleaner shrimp and hermit crabs are thriving. I'm getting tired of killing livestock.


JohnD

 

[Jaybird]

I would toss a couple of raw shrimp into the tank to let them rot and keep your filters and skimmer off. If your filters and skimmer are one you can reduce some of the nitrates. As the shrimp rot you should keep testing your water for ammonia, nitrite, and nitrate. Since it's been so long since you've had fish in the tank it probably needs to cycle again. The raw shrimp will rot and produce ammonia, which you should be able to see in the tests. A shrimp and a couple of hermits will not produce enough ammonia to keep a 75G tank cycled.

If you have enought live rock in the tank you probably don't need to have the HOB filters. How is your skimmer setup?

As well, what kind of test kit are you using?

 

[abrahamavelar]

also wat ill do just to play it safe ill be to empty the tank and rinse it pretty good and fill it up again and then ill put all the things back and let it cycle again