- Joined
- Nov 9, 2014
- Messages
- 22,424
- Reaction score
- 34,850
Why couldn't you do it in hypo...?
Taken from here: http://www.reefsanctuary.com/forum/index.php?threads/copper-treatment-use-problems.23130/
When copper ions get into our aquarium water, they will complex with several other salt water ingredients and some of the things we put in our aquariums. Copper ions, as noted above, are very fond of forming complexes with carbonates. When they do, this complex is not very soluble at the pH of our aquariums and it will precipitate, or come out of solution.
Copper ions will do the same with rocks and substrates that contain any form of carbonate materials. This is one reason why it is best to use copper medications in a bare-bottom hospital tank without live rock, dead rock, and carbonate based decorations.
The precipitated copper-carbonate will redissolve if the pH of the aquarium water goes down. This has the effect of suddenly increasing the amount of copper in the tank water. So, the aquarist thinks they are in control of the copper concentration only to find that there is a surge of copper when the pH drops. In addition to maintaining the effective copper concentration, attention has to be given to the holding the pH of the water steady. By the way, this surge in copper, no matter how short of time it is, is enough to permanently injure, poison, or kill the fish being treated.