Did low salinity kill all my corals?

[RyanReef]

Hey all, so I have been reefing for almost a year now. I have a 24g AIO with 2 clowns (now 1), a watchman goby, and a pistol shrimp. And then a handful of blue-leg hermits, nasarrius snails and some random other snails.

I had several assorted LPS,  mushrooms, 2 rock anemones, some duncans, and some zoas in the tank.

I usually keep my salinity at 34-35 PPT. Over Christmas we got a nasty flu that kicked our asses and I barely left my bed. Unfortunately, I am thinking my Hanna pen needed calibrated (I suck) when I did my last water change, before we get ill, because when I finally came around and tested it after a few days, my salinity was at like 23 ppt and everything in the tank was looking pretty pissed! The irony....my new ATO came while I was sick and just sat on my desk.

 

I have gradually gotten it back up to 34 ppt with water changes, but the damage is done. EVERYTHING, except 3 mushrooms looks to be dead....including my one clownfish.

My ammonia is 0, trites 0, trates 10. That is all I really test for.

Is it safe to say that the salinity swing is officially what killed everything? If so, do I need to wait until I started adding corals back?

[mcarroll]

I'm not sure I understand.

 

Is the thought that your pre-flu water chage was mixed incorrectly due to a testing error?   Hm...  🤔

 

Checking this calculator it looks like it would take a 50% (11-12 gallon) "all pure water" water change to make the salinity drop to 23 ppt.  I'm not sure this sounds like a testing error.

 

Also, I don't get the connection with the ATO.  Without an ATO the reef's salinity would slowly go up, not down.

 

I am probably missing something.

 

2 hours ago, RyanReef said:

My ammonia is 0, trites 0, trates 10. That is all I really test for.

You should also be testing for phosphates if you're keeping corals...need to avoid hitting zero.

 

It should be safe to add corals again once you have a lock on how salinity got SO out of whack....which you might understand, but currently I don't. 😉 

[RyanReef]

2 hours ago, mcarroll said:

I'm not sure I understand.

 

Is the thought that your pre-flu water chage was mixed incorrectly due to a testing error?   Hm...  🤔

 

Checking this calculator it looks like it would take a 50% (11-12 gallon) "all pure water" water change to make the salinity drop to 23 ppt.  I'm not sure this sounds like a testing error.

 

Also, I don't get the connection with the ATO.  Without an ATO the reef's salinity would slowly go up, not down.

 

I am probably missing something.

 

You should also be testing for phosphates if you're keeping corals...need to avoid hitting zero.

 

It should be safe to add corals again once you have a lock on how salinity got SO out of whack....which you might understand, but currently I don't. 😉 

Honestly I have no idea how my salinity got so dang low. I assume it was when I did a water change before we got sick... But yes not sure how I f'd it up so bad.

The ATO had nothing to do with this situation I was just saying it's kind of funny because those are meant to somewhat help you keep your salinity in check. I understand it wouldn't have helped me in this situation.

[mcarroll]

41 minutes ago, RyanReef said:

Honestly I have no idea how my salinity got so dang low. I assume it was when I did a water change before we got sick...

How long do you think the salinity meter was "off calibration" before this?  How many "off" water changes could there have been?  Just one?

 

How big of water changes are you doing?

 

If you're doing 5 gallon water changes, there needs to be [5 gallons * .5 cups =] 2.5 cups of dry salt mix per bucket.  Does this sound like the rate you've been mixing for your saltwater? 

 

5 hours ago, RyanReef said:

Unfortunately, I am thinking my Hanna pen needed calibrated (I suck) when I did my last water change

Is there any chance that your 23 ppt reading was still incorrect?  Do you have a standard hydrometer or refractometer to compare with?

 

 

[seabass]

23 PPT (a specific gravity of 1.017) shouldn't kill a clownfish.  But, yes, that could be hard on inverts (especially sensitive ones).  However, like Matt, I'm guessing there was an additional problem (something that you weren't testing for) that might have also contributed to the deaths.

[RyanReef]

20 hours ago, mcarroll said:

How long do you think the salinity meter was "off calibration" before this?  How many "off" water changes could there have been?  Just one?

 

How big of water changes are you doing?

 

If you're doing 5 gallon water changes, there needs to be [5 gallons * .5 cups =] 2.5 cups of dry salt mix per bucket.  Does this sound like the rate you've been mixing for your saltwater? 

 

Is there any chance that your 23 ppt reading was still incorrect?  Do you have a standard hydrometer or refractometer to compare with?

 

 

I do about 4 gallon water changes every week on the 24 gallon tank.....which really has about 17 gallons of water in it.

Yes that sounds about close to what I mix when I do saltwater, give or take. I honestly don't know how long it was messed up. It could have been 2 water changes. I doubt more than that.

[RyanReef]

18 hours ago, seabass said:

23 PPT (a specific gravity of 1.017) shouldn't kill a clownfish.  But, yes, that could be hard on inverts (especially sensitive ones).  However, like Matt, I'm guessing there was an additional problem (something that you weren't testing for) that might have also contributed to the deaths.

So most likely there was something that already weakened everything and then the salinity drop was the nail in the coffin. Makes sense.

And here I thought I'd make it the whole year without any of those newbie horror stories. 

 

Appreciate the replies

[mcarroll]

3 hours ago, RyanReef said:

I do about 4 gallon water changes every week on the 24 gallon tank.....which really has about 17 gallons of water in it.

Yes that sounds about close to what I mix when I do saltwater, give or take. I honestly don't know how long it was messed up. It could have been 2 water changes. I doubt more than that.

I don't see that adding up to the salinity drop you first reported then....if you had mixed almost-pure freshwater instead of full-strength seawater there wouldn't be a mystery....just a "Doh!".

 

This makes me question your salinity readings again – both before and after the "event".

 

Do you have a LFS or reef buddy who can double check your readings?

 

3 hours ago, RyanReef said:

And here I thought I'd make it the whole year without any of those newbie horror stories.

I say get them out of the way sooner than later...less potential for damage.

 

Here's my main goof...took me almost 5 years to commit it...way more damage that can be with done 5 years of coral growth:

Alk precipitation....anyone else been through this?   I'm pretty sure this was just a plain old sleepy-headed goof up....working on the tank late at night. 🤦‍♂️

 

Unfortunately that wasn't my only goof...

 

There isn't really a good thread documenting the next one (which was around the same timeframe...several years ago) but my switch to LED's from halides was not smooth.  I lost most of the giant corals you can see in this thread.  Lesson learned?  Use a light meter when switching your reef's lighting – any light meter is better than none.  Internet advice is not a  good substitute. 😉 

[RyanReef]

So I did get a phosphate checker. They came back at .31. Is that super high?

[mcarroll]

It's on the high side of normal, but there aren't any real issues with it being"high".  

 

The issues all happen if it goes to 0.00 ppm.

 

Hopefully we can finish adding up the clues to what happened with salinity since that seems to be that main/only problem...

[jcrisman2009]

On 1/11/2022 at 8:18 AM, RyanReef said:

So I did get a phosphate checker. They came back at .31. Is that super high?

Yes! You might consider purchasing some phosphate remover ASAP or do multiple water changes to SLOWLY bring it down to at least 0.1!