Tank crashed.... what to do??

[N0okie]

My tank that had been up and stable for around a year crashed last night. I woke up to find all of my fish dead. Some corals, shrimp and hermits are alive. The only possible causes of death that I can think of is because I ran some new piping to the sump yesterday, and maybe the pvc glue somehow leeched into the system (it may not have been fully dried.) Or, my sea apple may have died first.
So now, what precautions should I take before restocking? Do I need to just change the water, or is this going to require new sand and cleaning the rocks somehow or what?

I'd appreciate any and all help. Thank you.

RIP
Blue Damsel
Yellow Damsel
Black Damsel
Pair of Oscellaris
African Yellow Bellied Hepatus Tang

Pulsing Sinularia
Toadstool

Sea Apple
Many Snails

 

[Bandsaw]

I have survived a tank crash before. It is amazing just how fast the tank will recover.

I would first try to determine the exact cause. Certainly the sea apple has the potential to wipe a tank out if it died first. If the plumbing, make sure the PVC glue has cured and is rated for drinking water systems.

Run lots of carbon and skim well. I don't beleive you need to change the sand or the rock.

Water changes would be in order. I would say 20 to 30% now and another 15% until all the die off is gone and your parameters are looking good again.

 

[Fuegofish777]

I'm really sorry to hear that. All you can do is keep on goin. I would suggest many water changes. dont change out 100% of the water at once, maybe do the first one like 40 or 50%, then from there do abotu 25% changes. This should take care of all the nutrients from the dead fish and corals. Just make sure to do the first one ASAP if you want to save whats left. IME you can use the same sand and rock, as long as you are sure they werent the cause of any problem. HTH good luck