Goby bonded pair question


New member
So, I've been keeping yasha pairs for about a decade. Great luck pairing them up. Actually had one female that lived to a very ripe old age for a small goby, and had a couple mates during her life! They even bred.
At one point kept multiple pairs in a 30 gallon, and never had an issue.

After losing her, I decided to try something different and got a bonded pair of draculas from DD.
Woke up the first morning to find one extremely torn up, and it died later that day of it's injuries. I blamed my small ocellaris clown, and banished her to a different tank. Saw the second dracula again a couple days later with a jaw busted so badly that it was never able to eat again, and died soon after.
Blamed myself for it a lot, convinced it was the clown.

Been a while, and I ordered another bonded pair on Diver's Den. (Which, by the way are coming in SUPER small, not sure if this is a common thing!)

Within the first day, they were literally at each other's throats. Spent hours trying to separate them after I found them lockjawed together, thrashing around. It's a 30 gallon tank and the fish are about 3/4", but they will NOT leave each other alone. One's dorsal is torn so badly it's just a couple spines, and I assume it will never recover.

I've always had such easy luck with pairing yasha's, clowns, pygmy filefish, etc... I've been shocked by this in fish I'm buying as bonded, especially such juveniles.
I assume this is what happened to the first pair now, as well, as the clownfish isn't in there and always was perfectly harmless to even new fish.

Any suggestions or if I'm doing anything wrong here? They ship separately, and I acclimated them separately, then added them to the tank together with their shrimp.

I'm trying to find a good home locally for one of the dracs, but he's not pretty to look at anymore.