Khulis dying due to temperature change?

Hello all,

We have a 20G fully cycled, heated, planted tank that is 16 months old. We have 11 tetras and had 5 khuli loaches. They're in my daughters room, and due to a window being left open the tank dipped from 77C to 72C last night. I thought nothing of it, because we have a heater, but I was horrified to see 3 dead khulis on the gravel. One is in hiding, and the remaining one is kind of laying on the gravel in a corner, breathing slowly. It almost seems to have faint areas on it, suggestive of shed skin. The tank is back up to regular temperature but otherwise, I am unsure what I can do for this guy, beyond clean water, good conditions, and time.

I did a deep clean a few days ago, which caused an ammonia spike (2.0ppm) and so did a 50% water change to bring that down to as close to zero as possible. I've been monitoring and dosing with Seachem every 24 hours or so.

My wife and I feel absolutely horrible, but I'm trying to determine if this were due to an ammonia spike slipping past me, or the 5C temperature change. My suspicion is that it was both combined that caused this.

 

Doing a deep clean in any tank is not a good idea, especially if you end up changing the filter media and/or cleaning all the substrate. The ammonia spike could definitely kill fragile kuhlis but the temp drop could do the same.

I had my heater die in a tank with kuhlis around Christmas, didn't realize until all but a couple loaches were dead. Temp dropped below 70 as it was winter and they were in the basement. Always have a heater for tropical fish and be sure to check the temp every now and then. Just touching the glass is often how I check to see if the heaters are working. Probably why I have lots of finger print too...

 

tropical fish can survive 1 or 2 days at least with 10-15F degrees below their normal comfort zone temperatures. it happens in their natural habitats from time to time also. short term cold snaps of a day or two or rapid drops of a few degrees out of range, might make them lethargic, but it won't kill them. they would die by day 3 of it though if it were prolonged.
We get this sometimes in South Florida with all the non-native tropical fish in the waterways, one or two days of a cold snap is fine, day 3 of it, there's a whole bunch of floaters all over. it would really need to get to 65 or lower to kill tropicals after a couple days. or much colder than that, like 40s-50s for it to kill in less than a day.

Khuli have soft thin scales, and no scales on their heads, it's more like a skin than scales. I would think if anything killed them off overnight it was a spike that did it, damaging them first, and the weakest dying first. they kind of have a rough time with bacterial infections if they get any injuries.

Weakened injured fish, struggling, the temp change would not have helped any for sure, but it wouldn't be the cause.

Not sure what you mean by deep clean? I vacuum my substrate and change 50% of the water, clean the glass and objects, at least once a week, I would consider that a normal clean. I'd do filter maintenance on a different day though, I wouldn't do everything on the same day,. A light clean might be, changing water and just wiping the front glass.

There shouldn't be any ammonia spike from cleaning, or you're doing it wrong. fish tanks should be clean and presentable, but the last thing they need is to be made sanitary.

 

Thanks for getting back to me. Unfortunately, 3 died overnight, and the other 2 are in hiding.

I'll try to explain what I mean by deep clean: I did a solid vacuum of the dirty gravel (not all the way to the bottom, but did pull up a surprising amount of gunk), trimmed and clipped any brown or dead leaves, and scraped the glass. I also did a 50% WC afterward, and was careful not to just splash it into the gravel and kick up a lot of stuff. The filter was left alone, and half of the substrate was left alone. This was Tuesday, I want to say? By Wednesday, the water was clearer than I'd seen in months. All of the fish appeared happy, too. I still tested the waters and was horrified to see 2.0ppm ammonia. And that's where we are today.

I won't lie, I read a lot about how people lose khulis, or that they can be finnicky and in 16 months of fishkeeping (and making every newbie mistake along the way), we'd not lost a single one. Thanks to PetsMart, we did a fish-in cycle, relied on them for water parameters, and somehow the khulis survived all of that and I suppose I'd just never imagined that we'd be here.

 

I've been monitoring and dosing with Seachem every 24 hours or so.

I assume you mean Prime. There is no reason to do this, and it can deplete the oxygen in your tank and kill your fish. It does nothing to protect the fish from ammonia and should only be used to dechlorinate your tap water in an amount to remove the chlorine. It is just a dechlorinator.

Here is a thread where you can see someone's measurements of oxygen in their tank after adding too much Prime. This is well known in the fisheries and aquaculture world and water treatment.

Very odd fishless cycle parameters | Aquarium Nitrogen Cycle Forum | 520496

There is no way that the temperature reduction killed your fish. But ammonia and lack of oxygen will kill fish.

If you have been dumping Prime in please understand that this can deplete the oxygen to the point where it can slow your cycle too. The cycle needs oxygen as well.

 

That's news to me! The bottle that I have specifically indicates that it's a water conditioner that removes chlorine and chloramine, and detoxifies ammonia, nitrites, and nitrates. As a practice, whenever the ammonia went up, I'd always do a water change, and add a small dose if needed (appears that it wasn't).

I'll need to look into this further. So, if the addition of Prime doesn't protect fish from ammonia, why would they advertise it as such? Or maybe, why is there such a common belief that is how the product works? To be frank, I came to that conclusion from reading a lot of sites, and forums like this one.

 

That's news to me! The bottle that I have specifically indicates that it's a water conditioner that removes chlorine and chloramine, and detoxifies ammonia, nitrites, and nitrates. As a practice, whenever the ammonia went up, I'd always do a water change, and add a small dose if needed (appears that it wasn't).

I'll need to look into this further. So, if the addition of Prime doesn't protect fish from ammonia, why would they advertise it as such? Or maybe, why is there such a common belief that is how the product works? To be frank, I came to that conclusion from reading a lot of sites, and forums like this one.

There's two camps, believers and non-believers. The ammonia gets bound into a larger molecule that the fish can't absorb. it still shows up on an ammonia tests so people say it does nothing to it.

I've used it, I've needed it, it protected my fish from ammonia, I'm a believer and I still use it. It's not to be used in place of water changes or allowing ammonia to run, but as a safety net or in an emergency along with an immediate water change.

Believe or don't believe. Everyone has a choice
Overusage/overdosing of any oxidizer, like a dechlorinator, can cause oxygen depletion, prime or any other brand. Prime gets into more trouble because it's concentrated, you aren't paying for 90% more water like the other brands.

 

Seachem carefully says that Prime only detoxifies ammonia up to 1.0 ppm.

However, 1.0 ppm is NOT toxic to fish (unless you have very high pH).

So by their own claims, Prime does nothing.

 

To help summarize what's been said here, and also to help my own processing of it so it doesn't happen again:

1) Ammonia rose perhaps due to substrate being moved, part of my cleaning routine, or some other unknown factor.
2) I did a water change, and dosed with seachem (the highly concentrated one)
3) Unfortunately removed enough oxygen so as to crash the cycle, and cause ammonia to spike (2.0ppm)?
4) Spike caused significant injury to the java loaches; 5 pristella and 6 cherry barbs seemingly okay.
5) Java loaches die, ammonia moving in right direction (0.25ppm and dropping)

Things we all agree on:
1) SeaChem Prime removes chlorine and chloramine

Things we disagree/are unsure on:
2) SeaChem Prime turns ammonia to ammonium, which is harmless to fish and can be safely processes via BB in time; however, this will still flag as high ammonia on most tests.

Apologies for being pedantic here, I just want to be 100% sure, or at least clear on how to avoid this in the future.

Update: just did a 20% WC to bring down the ammonia, mindful of what I've learned about SeaChem. Dosed the minimum amount to remove the chlorine from the tapwater, and then preformed the change.

Prior to this I was going to look for the final, missing loach. I removed an artificial cave and to my incredible surprise, he popped out and swam about the tank. He was spooked, but fine! I placed the cave back and then proceeded with the WC.

How could he have survived? Does the ammonia disperse evenly throughout the entire water column, or does it pool along the bottom of the tank; since he enjoyed a "raised" cave, he thusly avoided the worst of it? He's also never looked like the rest - truth be told, they all appeared to be Pangio oblonga, based on an internet search, whereas this one appeared to be Pangio anguillaris, being longer, thinner, and of a gold tint.

 

Seachem says very clearly that Prime does NOT turn ammonia into ammonium. That is also very easy to test for. Prime has no effect on ammonia.

 

How could he have survived? Does the ammonia disperse evenly throughout the entire water column, or does it pool along the bottom of the tank; since he enjoyed a "raised" cave, he thusly avoided the worst of it? He's also never looked like the rest - truth be told, they all appeared to be Pangio oblonga, based on an internet search, whereas this one appeared to be Pangio anguillaris, being longer, thinner, and of a gold tint.

Not every fish is built equally even if they are the same species (or maybe different in this case?).
Whatever happened though it sucks. Kuhlis are great it's a shame to lose them. Glad you have at least one left and the tank isn't out of control