Cory issues

My girlfriend and I bought 3 orange laser corydoras on Wednesday. This morning I found one stone dead, and I'm trying to figure out what went wrong. I drip acclimated them for about an hour. Water this morning read 0 ammonia, 0 nitrite, 10ppm nitrate and was treated with Seachem Prime. There aren't a ton of hiding spots in the tank (driftwood is shipping in on monday) so I added a mug as a makeshift cave.

Now that I have two, I'm kind of at a crossroads. I don't want them to die of stress due to not having a school, but at 15 a pop I want to make sure they don't keep dying. I've read that different species of cories will school together, so would buying a few less expensive (possibly hardier) cories help them out? Should I just wait it out and see if these two make it before adding more?

Have a picture of the tank setup? What's the pH and hardness also? I think is a fairly new setup yeah? Also what temp are you running?

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There's java fern all over the place. Someone gave me a abunch with another plant so it's just floating around until monday.


Tank is pretty new, but I've been trying to keep a pretty good eye on it. I haven't been monitoring the pH and hardness as much, but last time I had a pH at around 7.0-7.2. I can't remember hardness; I'll retest when I get home, but I don't remember it being particularly hard. Running at 75F.

Also, I've been having trouble getting them excited about the Repashy super food I bought, not sure if it's related. It's the shrimp kind.

My corys love the Hikari sinking pellets. Sorry for your loss

With that info it seems like it should be thriving. Maybe the tank just isn't as stable as they'd like yet or something.

Sometimes fish just die of shock after a move. It is just one of those things.

Thanks for the input, very appreciated! Yea, I guess I'll just chalk it up to vengeful aquarium gods unless something else happens.

I don't want the two left to die of stress, would buying a few cheaper cories for them to school with prevent that? Should I just wait it out and see if these two make it and just get more lasers? Am I overestimating the stress danger?

"so I added a mug"

Any chance that mug had soap residue on it? Just a thought.

I think you're overestimating the stress danger yes.

Another dead one this morning leaving me a lone survivor.   I guess my cory fix is going to have to wait until the tank is older.

Yeah I'm not sure whats going on for you. I have 2 tanks of lazers doing just fine at the shop here. Something odd for sure.