"Cobwebs" seen on fish, now everything dead??

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RLG2182

Aquarium Advice FINatic
Joined
Jan 2, 2005
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Rancho Cucamonga, California
"Cobwebs" seen on fish, now everything dead?? (issue with silicone?)

So. Yesterday was a bad day. Just when you thought you had everything under control...

This last weekend I upgraded from a 125 to a 140 gal that was much better imo. The 125 was up and running for a year since I upgraded from my old 60 that was running for 5+ years. Did the usual: saved all the water, cleaned out new tank with ro/di water, no soap, soaked all pumps in vinegar and rinsed with ro/di water. Put all LR in holding tubs filled with water to minimize any die off watsoever. Put sand in holding buckets with water. Fish in a 40 gal aux tank. They were all in there for 24 hours.

Got new tank set up, put everything back in the tank slowly, ran filters 'til water was less cloudy. Filled the rest of the tank with fully mixed saltwater from 55 gal holding tanks in my garage. Made sure silicone on new sump config was dry and ready. Moved fish in last and everyone seemed ok.

Yesterday I woke up, all fish were accounted for. BUT... my cleaner wrasse was covered in a kind of white "cobweb" thing all over his body. No white spots like ich or anything I've ever seen before. He was still moving around normally, as were all the fish.

I came home after work to find my tank barren. Only my two clowns were still alive. ALL other fish died, including my brittle star that just died today. The clowns seem fine with no spots on their bodies and no sign of distress.

Tested my water immediately:

Amm -0
Nitrite -0
Nitrate -10
Temp -80
Sal -1.025

I just have no idea what happened. All fish were perfectly healthy before the tank change. Could something have contaminated the water during the change? The only "warning sign" I ever saw was this cobweb type thing... unfortunately I didn't take any pictures of it before I took it out of the tank. The other thing I did notice was patches of chaeto from my fuge did look a bit limp compared to the rest, as if maybe there was die-off? A portion of it was left out of water for 24 hours by mistake.

Losses:
Foxface
Powder Brown Tang
Blue Tang
4 Green Chromis
Cleaner Wrasse
Brittle Star

Any thoughts?
 
Not sure what caused the deaths, but don't Cleaner Wrasses spin a cobweb-like "cocoon" to sleep in? I'm thinking this is what you were seeing on the wrasse.
 
did you reseal the tank or add any silicone?

Yes. My sump is a 60 gal glass sump with glass baffles. I repositioned the baffles and added new silicon to seal it. It cured for 24 hours and was water tested, then dried out again, cleaned, and added to the bottom of the tank. Same silicon I used for my last tank with no issues.

don't Cleaner Wrasses spin a cobweb-like "cocoon" to sleep in?

"Cleaner wrasses sleep in crevices between rocks or corals, covered in a slime layer that is secreted at dusk. In the morning these can be seen floating on the surface." ~~ Wikipedia

Never knew that from the Wrasses... didn't notice it before, but definitely interesting! Does leave more reasons for doubt. Also don't know what could kill off such big & healthy fish and a brittle star, but why two clowns (and an engineer goby I forgot to mention) would survive. :confused:

I did test my water yesterday from my ro/di and it did read 10ppm. Although it is higher than I'd like (and time to replace filters I'm sure), I'd hardly think this could affect anything especially if this was the same water I used to use in my auto top-off as before.
 
Is it the exact same tube you used as last time? What brand? It's the only thing that is sticking out at me right now as a cause besides maybe you stirred up something really nasty with your sand. But If you nitrates are only 10 then I doubt it was that.
 
Is it the exact same tube you used as last time? What brand?

Not the same tube... got a new one from the store. GE brand clear 100% silicone II, "dries waterproof in 3 hours" one. Also used a 1/2 tube of actual (expensive) "aquarium silicone" but I've been told it's really the same thing as long as you use 100% silicone. I used this before with my last tanks with no issues. I also used weld-on 16 to bond an acrylic center overflow box to the acrylic tank but that was also allowed 48 hours to cure, water tested, dried, cleaned.

Any thoughts on the possible die-off on the chaeto? I wonder if there's something that clowns are immune/resistant to that others aren't in comparison.
 
I don't have a SW tank, but this is an interesting quandary, so I did a little research and the closest thing I could find was this:

Brooklynella: An equally dangerous variation of Saltwater Ich, the primary difference being that Brooklynella appears as a more wispy texture to the fish, instead of the classic "salt granules" of Ich. Brooklynella is most commonly carried by Clownfish, however in many cases of Brooklynella outbreaks - the clownfish are the only survivors.

I'm not sure if this is the culprit, because I think ALL of your fish would've ended up with the "cobwebs" - and Brooklynella also doesn't usually kill that fast.
 
hmmm... Brooklynella... would mean that the clowns would host it and others would get it? Seems like this would be that the clowns would die off first... couldn't find much but didn't seem like this was an instant killer. Good to know since I so have clowns

Thanks for the replies so far!
 
GE silicone II has an anti mold & fungus agent in it that is super poisonous. GE silicone I for plastics is the only aquarium safe silicone i know of that GE makes. I believe the change was within the past couple years they added something called "bioseal." I could be wrong, could you post a link to exactly what you got?
 
Found this link to Lowes, although it was purchased at a different store.

Shop GE 9.8 oz Silicone II Premium Waterproof Window & Door CLEAR Caulk at Lowes.com

I've been reading and from what I can tell there's two different kinds of GE Silicone II: Window & Door + Batch & Kitchen. From what I read the Window & Door Silicone doesn't have a mold inhibitor, but I could be wrong. I'll go to the store and double check. I used this before in the hand-held tube version and didn't have any issues. There are however MANY forums with people questioning if it is aquarium safe with mixed opinions either way.
 
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So I just went to the store and got a few different tubes of silicone. Both the GE Silicone I window & door + Kitchen & bath say that they release acetic acid while curing, while GE Silicone II says it releases methanol and ammonia while curing. All of them say it is not for use below the water line or in aquariums (legal disclosures, I'm sure. DOH!). They all mention some kind of mold free protection:

Silicone I: For a long-lasting seal, choose 100% silicone, not acrylic caulk, which can shrink and crack, leaving gaps for water to seep through. Those leaks can lead to water damage and mold growth.

Silicone II:100% silicone is a 3 hr. Rain-Ready and Sun/Freeze Proof caulk for windows and doors, as well as attics and basements, that also provides mold-free product protection.

Silicone II also mentions that it isn't for use below the water line, aquariums, AND where FDS compliance is necessary.

Thoughts? :confused:
 
Thats my guess man. If its the windows and door stuff it should be safe, but people say the II has to cure for like 3 days so it wont release ammonia and other nasties. The I is safer much earlier.

I'm curious why it wouldnt show in your testing, but its my main suspect at this point. Secondary would still be something completely random that your stirred up on accident or got into your tank.
 
*face-palm*

Yeah... I'm starting to think that it's more the fact that I only let it cure for 24 hours. Many say 48 to 72 hours, rather than the kind I used. I found other forums on freshwater tanks that someone used silicone to seal a rock wall and within two days his fish all died. Same with my fish: no visual signs other than the possible behavioral signs I saw while my foxface and blue tang were dying... difficulties breathing, swimming at weird angles, etc.

IF this is the case... I need new insight... if I take out the sump & replace the silicone, let it cure for the proper time, what else would I need to do? A 100% water change? Gradual water changes?

Now that I think of it I did use some on the overflow box as well but as this was permanently welded on with acrylic glue as well, it cannot be taken down & replaced. Does anyone think that these possible emissions will cease over time if left to dry longer?
 
yuck. sorry man this kinda stuff is always hard to hear about, and I'm sure more crappy to have it happen.

I don't know what to tell you about the overflow. I would take a razor and cut out as much of it as you can. For the sump, do the same and reseal it with GE I, Let everything sit dry for as long as you can. You might even consider draining your overflow box and a little out of your tank to bypass it, and just run a HOB for a couple days.

I don't know if eventually it will all leech out. I would be worried there is something similar to copper and maybe it is in your rocks and stuff now. But thats worst case, and I have no experience with that. Maybe someone else knows more.
 
I pretty convinced this is it. It's the only thing that was newly introduced to the system that could've killed the fish so rapidly. I'll start another thread on cleaning procedures...
 
Thank god no corals... YET. I've had a fowlr for the last 5 years and with this upgrade I was planning to add them. Although the fish were only about $150... I'm concerned about everything else as well: I have a ton of LR and LS, and the two clowns have been with me for 6 years now and really have become like family to us. First thing when I get home I'm going to put them in a quarantine tank with new water til this mess gets resolved.
 
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