Copper levels in QT -- re-dose necessary?

[ACBlinky]

Hi all, question about copper levels...
My QT has had copper in it for some time now, and I'm adding a new group of fish (woohoo!) and wonder if I will need to re-dose, or if the copper I added weeks back will be effective on any parasites these fish may carry... basically is copper indefinitely effective, or does it 'wear out' over time?

Thanks!

[wooden_reefer]

If the copper is the stable cheleated type, you may not have to add any more.

I always use straight copper and use pulses of copper instead of constant level.

[ridetheducati]

Originally Posted by ACBlinky

Hi all, question about copper levels...
My QT has had copper in it for some time now, and I'm adding a new group of fish (woohoo!) and wonder if I will need to re-dose, or if the copper I added weeks back will be effective on any parasites these fish may carry... basically is copper indefinitely effective, or does it 'wear out' over time?

Thanks!

Why not test to determine whether the appropriate levels are present.

[slajiness]

Just curious but what is a appropriate level for a 10 gallon QT?

[ridetheducati]

Originally Posted by slajiness

Just curious but what is a appropriate level for a 10 gallon QT?

Generally, 0.5 ppm.

[ACBlinky]

Originally Posted by ridetheducati

Why not test to determine whether the appropriate levels are present.

I tested and it looks like the copper levels zeroed out, but honestly I don't trust titration-type kits much and didn't want to add more cupramine if I didn't need to. The QT has been running with bio media (little rock-like cylinders, the type used for AquaClear HOB filters) and there are three shells as well as two polyresin rock structures in the tank -- I don't know how absorbent these materials are, but the copper appears to have gone somewhere.

I re-dosed cupramine today, to 0.5ppm (according to the test kit anyway) and the fish seem just fine. I'm planning a 50% water change tomorrow, so I'll have another opportunity to test the Cu level and re-adjust if necessary (I'll add to the replacement water and test, before putting it into the QT, so levels stay constant). Fortunately the fish show NO signs of disease, so I'll only have to worry about this for two weeks (the cupramine bottle says to keep the fish in treatment for 14 days), as opposed to the full 6-12 week exposure I'd need if they were 'ich-y'.