Get rid of them. Chances are it raised the pH to a high level, which is why the clown and cory's died becaus they love a low pH. The other fish would be more tolerant of the pH. A severe pH shock it prolly what killed them.
All the fish in my 29 died after adding decor??
- Thread starter STONEDFISH
- Start date
If they were fresh concrete paving 'stones' then they would have leached lime from the cement into your tank water. That does crazy things to the pH and hardness = dead fish 
You would have to treat them like a new concrete fish pond, let them soak for several weeks with a few changes of water. That gets most of the 'stray' lime out of them so they have little effect on the water.
Sorry you had to find this out the hard way
Ian
You would have to treat them like a new concrete fish pond, let them soak for several weeks with a few changes of water. That gets most of the 'stray' lime out of them so they have little effect on the water.
Sorry you had to find this out the hard way
Ian
