Thoughts on unnexplained (and very sad) die-off

[gregzz4]

Sorry to read about your losses

Sounds like a cascade effect
Low Sg starts killing inverts and other sensitive life, ammo levels start to rise, bacteria starts to die off faster, more ammo, fish who are OK fighting off whatever is present in good water start to succumb to things their lowered immune systems can no longer deal with
Add the Prazipro and possibly this was the final straw

Prazipro can raise pH. Ammonia from die-off combined with higher pH can be lethal at much lower levels than our target pH would normally allow us to get away with

Just my thoughts

As far as proceeding goes, have you been testing for a cycle ?

[jostafew]

Thanks for the feedback gregzz, I've done a couple ammonia tests before and during the transition but they've always come up with nothing. I've also got one of those ammonia monitor things in the tank now to watch for any remaining issues but it has always read zero as well. To be honest I don't expect to see a cycle in the new system as it's 50% new water, all of the rock and sand was from a mature system, and all of the LR was scrubbed pretty vigorously (in tankwater) to remove any of the pest algae that had previously developed. But I have nitrite and nitrate test kits as well and will do a few tests here and there to watch for any changes over the next week or so.

[kien]

Sorry to hear if your loss. The hobby is hard enough as it is but to loose your tank inhabitants like that is a real kick to the nads :-(. Been there.. :-(

When you treated your tank with prazi pro did you turn off your skimmer like the bottle suggests? If I recall correctly the instructions say that you should turn off your skimmer. This is likely due to the fact that your skimmer could skim out the meds making it less effective. HOWEVER, I personally would not recommend doing this as turning off your skimmer for a period of time can dramatically reduce the oxygen in your tank. Mind you, if you don't have a skimmer then this is a non issue.

My recommendation when using meds with a skimmer is always to take off the skimmer cup and let it overflow into your sump during the treatment period. Assuming you have a sump of course.

[howdy20012002]

sorry for your losses..it always sucks when you lose things unexpectedly or for no apparent reason.
to be honest, I don't think that the SG at 1.021 would have killed the inverts if it had been a gradual reduction.
I would look elsewhere for the cause personally.
I am not sure what to suggest beyond that.
good luck
Neal

[Madreefer]

Originally Posted by howdy20012002

sorry for your losses..it always sucks when you lose things unexpectedly or for no apparent reason.
to be honest, I don't think that the SG at 1.021 would have killed the inverts if it had been a gradual reduction.
I would look elsewhere for the cause personally.
I am not sure what to suggest beyond that.
good luck
Neal

I totally agree with you and hoping someone else would respond first. I had a debate with another member about SG last week. Most stores keep their sg at 1.021.

[jostafew]

Thanks for the feedback guys. Neal, that's a good suggestion about keeping the skimmer running but taking out the cup. I did turn it off for the 12 days during treatment as recomended, but you're right I could have left it running (though not functioning) for oxygenation.

As for the SG decrease, yes it would have been very gradual, over the course of several months.

[albert_dao]

So... Were you using Reef Crystals?

[gregzz4]

Originally Posted by Madreefer

I had a debate with another member about SG

Me
I only mentioned the Sg possibility as the OP stated he lost inverts first, and I'll agree a gradual drop most likely was not the cause

I'm sure there's something out there, but I'm not aware of an infection that kills both fish and inverts. Maybe someone else knows ?
I say this as it still sounds to me like some kind of exposure or contamination

Do you remember using anything last summer that you'd not previously used ?

[howdy20012002]

I don't think it is a disease personally.
I don't know of any disease or parasite that can kill both fish and inverts.
IME typically inverts are fairly resilent to disease.
I think it must be something with the conditions of the tank
perhaps a contamination?
are your corals doing okay? what kind of corals do you have?
did you add any rock recently and did you test for copper if you did.
LR can hold copper and it will leech slowly back into your system.
I would definitely add carbon to see if you can contain any contaminents.
although the copper wouldn't affect the fish, it would definitely kill your inverts..and alot of other things such as bristle worms, amipods etc...
do you still see the critters swimming around your tank when the lights are off? see bristle worms when you feed? or any snails or crabs still alive?
if not, then I would definitely suspect copper...(although if your corals are doing fine..probably not copper either)
this die off could certainly cause the conditions of your tank to go south..which in turn would make your fish more prone to disease that they had previously been able to fight off.
however, diseases aren't something that linger around in your tank without being noticed...most diseases will either become noticeable or not.
so if you haven't noticed any disease symptoms within the last 3 months, not really sure what could be killing beyond something in your tank.