Help tank is crashing??? not sure why

[malalite]

I have a mature 3+ 125 long saltwater reef tank. My salinity was high I noticed this weekend around 1.030. I did a water change and lowered it towards 1.025.
1 day later water got really milky white cloudy... then we noticed a ton of flatworm deaths... We had 1 pink-green cucumber that looked like it was dying, so I took it out of the tank just now. I checked all my numbers and ammonia, nitrate, nitrite ect are all fine. The fish are dying, and it appears like they can not get enough oxygen. I have added a bubble machine that I keep for power outages, but they are really having trouble . I did a 45% water change it seemed to help for a little bit but still having troubles. I put all new carbon in during the water change as well.

[Tat2demon]

Im not certain but if the change in SG killed off a lot of flatworms I suppose they could release enough toxins to effect your fish. I know it can happen when people kill off large numbers with that flatworm exit stuff. Id say keep with the carbon, air pump and maybe a poly filter too. If everything else in in line I dont think theres much else you can do.

[Porcupinepuffer]

Agree with above post. too many flatworms that die off at once will make the water toxic. Run carbon. Try and remove as much of the flatworms as you can. Do more water changes after you've tried to get as much of the flatworms out. I'd just focus on keeping a stable salinity and PH while doing water changes for now and see if you can help what's left. Good luck... When you noticed your salinity was too high, it's safest to very slowly bring it back down. It probably reached that high point slowly and everything adjusted, but by trying to bring it down too quickly can cause more stress then the initial high salinity in the first place.

[serpentman]

Although as tempting as it is to make knee-jerk reactions, anytime you find your parameters out of whack, its always best to make corrections slowly.

It's also possible that your cucumbers were stressed and subsequently released their innards which will also make for a toxic situation.

I suggest a regimen of carbon and water changes to correct.

[sedor]

I'd also agree that in your situation a couple more larger water changes are in order...daily if you have to. Your likely dealing with toxins so that and carbon are going to be your best bet. Hopefully you don't lose to much in the crash, I hate it for ya man.

[TripleT]

How do you suspect your salinity rose this much in a 125 gallon tank?

Without knowing more, it's hard to rule out faulty readings.

For example, maybe the 1.030 reading was false, and you've actually just lowered from 1.025 to 1.020.

What are you using to measure salinity, and how are you verifying the accuracy?

[malalite]

Thanks, I appreciate all the quick responses. I will do water changes daily. This morning, lost several chromis, a naso, skunk cleaner shrimp. Meta tang is hanging in there, I have not seen the rest of the fish yet as they are hiding (I hope). I will also keep my parameters stable as possible during the changes. The water is still very cloudy but a little better. Thanks again.

[njdevilsfan]

throw a poly filter in the sump just in case something got in the tank

[strike2867]

Is double checking that salinity with an LFS possible?

[Sk8r]

Move your surviving fish and inverts to quarantine tank with clean water with identical salinity: getting them to good water may save them and help your tank by getting their demands out of its stressed system.
Get an automated topoff system ( ATO)
Get a refractometer.
Whenever making salinity changes, it is best to proceed by means of topoff, ie, topoff with salt water to raise salinity, with fresh water to lower it, over several days. Once a salinity accident has happened, and fish are still alive, they have adjusted to the new salinity: too fast a correction is as damaging as the original accident, even if it ends up at a better place.

[Irvine Man]

Yeah I would check the salinity levels again to confirm you are on point there. I have three different refractometers and I always check it and then recheck and wash out with normal tap water and check again. I'm paranoid that a little micro bubble is throwing off the readings.

Good luck on your tanks recovery. Hopefully the tank is on its way back and not still crashing from the toxins of the dead worms.

[seapug]

I'm still curious about what caused this whole situation.
What kind of a water change did you perform to reduce the salinity and kill of the flatworms?

Was there a reason you simply didn't remove tank water and replace with fresh water over a day or two to bring it down?

[malalite]

I am not 100% sure what caused this. I am guessing it was because my salinity got up to 1.030. The tank is 125 gallons so it is not very quick to change 1 way or another. I did have a pink cucumber in the tank, and I am not sure if he died first or not. Regardless the cucumber died, then massive amounts of bristle worms died. I define massive amounts of bristle worms as 5 fist size groups, all flatworms are gone from what I can tell as well now. I put two aquaclear 500's on the tank after the suggestions and loaded both with fresh carbon. I also did another 25% water change last night bringing total to 4. All cycle numbers are still 0. An oddity to throw in to the mix, my wife dosed that day's Vodka, after I had already done so. Keep in mind the water was already cloudy before she dosed. I put in two air stones into the tank for additional oxygenation.
Tank looks much better today, cloudiness is almost gone. The surviving fish are looking less stress, but my invert population took huge causality’s. I lost my fox face, naso, powder blue, all chromis, small pacific blue, pearl scale butterfly, coral beauty.
Who made it? Yellow belly, red tail trigger, clownfish, scissor tail gobies, mandarin’s, Meta, cardinals.
Lesson learned, if fish are stressed and looking like they are not getting enough air, do not let lights turn off, everyone was alive until that happened. I would have done a bigger water change than my initial 45% and put the carbon/floss in larger quantity’s than I did.
As far as the suggestions, they helped a lot. And my wife and I are still going forward with our new system that the survivors are going to be moved too. I am building in controls to help prevent a problem in the future.

[89Foxbody]

I'm still not getting why you did a water change to lower the salinity instead of just adding fresh water. Also how did 125g of water raise .005 without you noticing? I'm not trying to be an *** but it seems like you should test more often.

Sorry about the loss of your fish. I know how frustrating it can be. Good luck with the recovery.

[clockman]

You said the pink cucumber died 1st. Cucumbers that have bright colors have been known to release toxins when stressed which can wipe out a whole tank. Stick with the dark colored cukes (they look like turds) they're not pretty but are safer.

[Porcupinepuffer]

You really had that tank jam packed with fish. Do you have a good sized sump and skimmer? Sorry for the loss.

[malalite]

I had more fish than I mentioned in there, still alive also are my Purple tang and a all of my blennies and some more gobies.
Yes I think it started with the pink cucumber and I found out after he was in the tank the risk. He had been fine for over a year.
I would have added water but after adding 5 gallons to top off the system it did not lower it much. I am not sure how it got to that height. I do a water change every two weeks. I use a refractometer which I know is working as I tested and made sure it zeroed out this year. I normally keep my tank at 1.025 for my goal. I do not have a sump. It is all hang on the back, I have two Remorah Pros with the upgrades.
I agree it should not have happened. That is why the system I am building in the basement (500gal plus) will have an auto top off unit as well as a water change valve and water empty valve. Plus the size should make swings much less likely.
As far as jam packed, I have a lot of fish yes, they were all happy and not once did I ever get a blip on my ammonia, Nitrate or Nitrite. Even with the fish death, I still am getting all 0's. When I built this system, I built it around what you could do to hold a lot of fish without a problem. It worked pretty well for not having a problem in 3 years. Yes all of the fish I have will outgrow this tank that is why I hope to have the new tank ready by Christmas time and then start phasing stuff over.

[Palting]

Glad to hear everything is getting better. Not sure about the sudden rise in salinity, but a stressed, or even worse a dead, cucumber can nuke a tank, the so-called "cuke nuke". I was looking into getting a tigertail cuke as a sand cleaner, until I heard about the innards of cukes nuking a tank. Hope you are not planning on getting one for your big tank.

[aleonn]

So sorry to hear. I hope things are stable now and continue to do so. I would continue to use a powerhead at the rocks, and siphon out dead flatworms and bristleworms if they're still lying around.

[malalite]

Yep I wish I took pictures of how many dead bristle worms there were... I would estimate take 4 baseballs worth of volume of worms..... I know they are hiding most of the time and a lot of them.... it was just kinda shocking... I added an additional powerhead to keep up the flow.
No more cucumbers for me, 1 experience is enough... I am good now...
I was thinking watch my cycle numbers and wait a month before doing anything with the tank... if anyone disagrees and think it should be longer let me know...
Thanks for the support.

[mscarpena]

That also seemed like a lot of fish in 125 to me. Glad things are turning around for you.

[aleonn]

Wow, 4 baseballs of bristleworms! That's pretty nasty! Good idea on waiting to put in any new livestock. That'll give a chance for the LR to repopulate from the presumed ammonium spike.