Dead efts, fungus--why?

[aquaria]

This might be a silly question, but it's something I've been wondering about recently.

We've kept fish and axolotls for a while, and every so often something goes wrong--and then comes the fungus. Recently we lost a batch of about 50 larvae to fungus over the course of 48 hours. It was really disappointing, they'd been growing well and were about a month old. (In retrospect they shouldn't have been sharing a water supply, but, live and learn.)

So where does fungus come from? It's easy to trace its spread between your own tanks and pets, but where was it before your first axy was sick? Is it in the air? Would air purifiers help? Is it a mystery?

(After the larvae fungus we preemptively treated our only adult axy. It's now two weeks later and he's perfectly healthy.)

 

[LSuzuki]

So, this is a recurring problem for you? Both fish and axolotls?

I don't know where it comes from for sure, but it wouldn't surprise me if there were spores in the water that accompanied your critters. It is impossible to totally eliminate them (out side of lab conditions, and probably not even then.) They probably are just waiting for an opportunity, as in, something to weaken the fish/axolotls.

Have you checked all of your water parameters when this is going on? High nitrate (and of course high ammonia and nitrite) can weaken your axolotl and make fungus infections more likely.

 

[auntiejude]

Fungal spores are everywhere - in tap water, in the air, in soil etc. you'll never get rid of it. If its a recurring problem with larvae you can try adding holtfreter's salts, it suppresses fungus growth without harming larvae.

 

[aquaria]

It's not a recurring problem, per se--we lost two axolotls in the same tank in June (ETA: same tank as each other, not the problem tank of the efts), though the third survived with salt baths etc, and then the whole lot of efts, which of course are smaller and succumb much faster. Fish fungus has only ever happened for us after injury. It doesn't spring up all over the place.

The water is always fine--we do weekly 20% changes on all the tanks, and the larvae get daily smaller changes. We were into fish for a while before axolotls, so we have tons of test kit supplies and keep primed and dechlor water on hand. I just wonder where it originates from.

auntiejude--thanks for the advice. We'll definitely try holtfreters salt if we try to raise from eggs again. Right now we're sticking to 4" and above--they're just hardier, and respond better to treatment.