Axolotl Post Mortem

Hello All fellow Axy enthusiasts,

Sad News. This morning I woke up to find my poor Montezuma (Golden one in avatar) had passed away at some point during the night. After a moment (or a bit more) of grieving, I checked on Carmen, the other axolotl within the tank. Luckily she was still alive, though fairly inactive just looking at Monty (maybe she was mourning the loss of her buddy?).

Monty's death was a surprise, so I have spent the day trying to think of possible reasons for this.

Water Parameters:
Ammonia: 0
Nitrite: 0
Nitrate: Did not have time to test this morning, but was fine last week.
pH: 7.5

Substrate: Course river sand.

Average Temperature: 21 degrees. I had tried as best I could to keep this down but full time work and australian summer made this difficult. (Ave air temp 30+)

Tank: 2 foot, 60L


Changes to the Tank leading up to this morning:
As Carmen has swallowed a rather large stone 2 weeks ago, I went about getting them off the rocks as soon as possible. I made up a bucket of their tank water and placed them in. I then made a smaller bucket of tank water for the filter media to go in (to reduce the loss of bacteria as much as possible). I then removed all of the tank water and the pebble substrate. As I purchased the tank second hand, it had rather ugly and uneven sky blue paint on the outside of the rear wall. I used paint remover to get rid of this while the tank had no life in it. (Axys and fish in bucket) All of the paint stripper was then vigorously washed away after all the paint had been removed.

After the paint stripper had been all clear as far as I could tell, I then added the sand and new tank water. I then carefully and slowly added the bucket of old tank water with the axys to acclimatise. Filter was then put back on and the tank started operating again, except with sand instead of gravel. (This would be an approx 90% water change).


Axolotl Diet: Frozen Bloodworms and once a week some frozen beef heart.

Axolotl Behavior: During these summer months, they have always been up at the top of tank (cooler water?). Intentionally floating. Carmen became bloated and struggled to move around since swallowing the stone, but this was to be expected. Monty liked to cling onto the frozen water bottles that were floating around. After being readded to the tank post-substrate change, they went straight to the bottom with limited movement. As I believe it, this is typical Axy behavior for new tank conditions (I rearranged some of the "furniture" while the water was gone).

Last week, however, Monty suddenly stopped eating. Nothing had changed within the diet. I fed him by hand, but he would just sit there and refuse to open his mouth with this wrigging clump of bloodworms there. His gills were pointed forward (stressed about something). He got thinner and thinner, which is when I started to worry. Average temp around 21.5 degrees at this stage. Carmen would eat every second day, which is less than usual but no cause of concern (as she was still eating something).

Last night, Monty suddenly displayed weird behavior. While clutching onto an ice bottle as he had done for most of summer... he suddenly let go and fell to the bottom of the tank upside down. It looked as if he had been shot. He was immobile at the bottom of the tank for 2 minutes and I was patiently waiting for some sign of movement. He sprang back to life and flipped himself over, with his mouth open. He started gliding around the bottom, so I assumed he was ok again. I went to bed and woke up to find him dead in the corner with his head over the air stone. Carmen on the floor at this point to, but still looking healthy (despite the stone).

So, with these facts in place, I am trying to find the possible causes of death (to ensure Carmen doesn't suffer the same fate).
What I have thought of:
- Temperature, Ave 21.5 degrees
- Some small residue of paint remover (highly toxic to everything, even for humans to inhale)
- The ice bottle may not have not been dechlorinated (mishap/forgetfulness on my part), and Monty had pried open the lid slightly while clutching onto it, causing chlorinated water to flow straight to his mouth and gills.
- Random ammonia spike last night (due to the 90% water change, and substrate change last week).

Am I missing something? Of those above, which seems most likely?

I would probably put it to a random ammonia spike, or perhaps a sudden change in water chemistry.

did you make sure that the new sand substrate was inert and won't mess with your tank water?

Well, I did do a shortcut with the sand and got "river sand" from the hardware store. This was because I needed the sand urgently and none of my LFS had enough quantity in stock.

The hardware store guy told me despite being 'river sand' it was from a quarry with nothing but sandstone in it. I still washed it completely though for about 6 hours before adding it to the aquarium base.

Could the loss of appetite over the past few days be due to a series of ammonia spikes or temperature? The ammonia reading was 0 ppm

I would probably guess that she still has some rocks within her that weren't passing due to her lack of willingness to eat and the temperature - you might consider fridging Carmen to ensure that she too hasn't ingested any as well as to reduce her stress

Park06 said:

The hardware store guy told me despite being 'river sand' it was from a quarry with nothing but sandstone in it.

Click to expand...

personally I would be skeptical about sand that comes from a quarry myself, just for the reason that it could be contaminated, but I do think that sandstone is inert, depending on were it comes from.

what does your axie's diet consist of?

you also imply in your OP that you had other fish in the same tank too, what type of fish are they if this is the case?

Ah, yes the other fish. Two rosey barbs that were from a batch of 6 added 4 months ago as feeder fish. They are the two remaining 'survivors'. They have grown quite large given their original size (they are approx 3cm in length). They spend most of their day in the corners wherever the axolotls aren't. Maybe that is why they have survived this long? However, in the past month they have actually been able to swim by the axolotls mouths during feeding time to get a bloodworm or two. Other than that, they have no impact on the axolotls whatsoever. There are 3 apple snails who also keep to themselves.

As i mentioned earlier. The diet was almost enitrely frozen bloodworms (as they were never interested in pellets to the point where the pellets would start decomposing and I would have to remove them). These bloodworms were fed by hand so the axolotls never did much hunting. Once a week I would chop up some little strands of beefheart as a treat.

I would guess it was the paint remover, but if your other axolotl seems fine then it probably wasn't. I think the swallowed stone might be a culprit. If you didn't have any ammonia reading then I wouldn't think it was an ammonia spike. With the decomposing Monty in your tank and no ammonia readings your bio bacteria is probably doing its job. As for the chlorinated water bottle, I woudln't think that would be the culprit. While chlorine is bad for fish, a small water bottle would probably not be fatal for an animal. I've heard of people doing 25% water changes with chlorinated water and they're fish being totally fine. I wouldn't ever recomend adding chlorine, but I dont think that was the culprit. Also I don't think your axolotl could actually unscrew the water bottle.

I'm sorry about this! Such sad news.

I myself completely agree with Carson...
Could it possibly be natural causes (i.e. old age)? Could it even just be the stress from the mini-cycle? Some axies just have a stronger immune system then others, so this could be why Carmon is OK.

I know this works for gravel, rocks, ornaments, driftwood, etc, so I assume it will work for sand -
To make sure the sand is inert, put some into a bucket with water, and pour vinegar on it. If it bubbles, it isn't safe.

Thanks for all the responses so far, and the sympathies. Not the first pet i have lost in my life, but the first which I feel responsible for the death.

Clarifying some other points:
Old age is unlikely, Monty was 2 years.
Carmen is the one with the stone in her belly, she is still alive.
Monty had no stones inside (that I could tell visually)

I spoke to my LFS guy today, and while they aren't experts on these things (especially axolotls), and told him the facts I have posted above. He said it was most likely temperature that got him, over time. This would make sense as the average temp was over their preferred maximum of 20 degrees... but I don't think it explains the sudden uncontrolled drop to the bottom of the tank he had last night, where it looked as if he had been shot.

So it leads me to another theory. Can axolotls (especially if they aren't eating) die from exhaustion?

Monty was always at the top of the tank swimming/trying to hold onto ice bottles, so he may "passed out" and fallen to the bottom of the tank, only regaining conciousness once he struck the ground. Assuming he kept this up all night while I was sleeping, he could have passed due to no more energy left in the tank?

Oh no Thats so sad, poor Monty.

I'm really no expert on things, but knowing just how dangerous stones and gravel are, it could well have been that Monty ended up with a stone or two stuck. Seems most likely

I know that colder water has more available oxygen, so the staying at the top might be to do with the temp, although, considering the weather over there I don't think 22 is the worst temperature axolotls suffer in oz. There are options for cooling, if you search the forum.

I'm not sure about the chlorinated water - but, if there was sufficient quantity, it may have killed off the bacteria which are responsible for the tanks bio-cycle, so you might want to check that nitrate reading, for Carmens sake.

The paint stripper - no idea how long it would take to be toxic, its been a week, you say?

I'm so sorry to hear about Monty, and I hope Carmen (and you) is ok.

x

Hows about the fact that pet axolotls are soooo horrifically inbred and there genetics are soo screwed up that It really could have been anything, a sudden major organ failure or something along those lines. Ive read abit about axolotl genetics (not alot I understood, twas just a flick through) but remember reading bits about certain genetic faults can cause heart or/and kidney failure, amongst other things.

Just thought I'd throw that one in there!

Hope you get to the bottom of all this!

Ed

Sorry you've lost an axie. I have no great insight to add - but I would suggest the LEAST likely of the suggested causes is temperature.

Agreed...my guys for the past two weeks have only gone below 22c once, and they're fine (Although today they're in a smaller tank at 23c, as their four footer was just below twenty five at 8 am-for comparison, the big fish tank in the main room was at thirty when we got home at two pm).
my thoughts are with you, hope Carmen's okay!