Water changes in QT with old tank water?

exnisstech · Oct 15, 2022

I don't think this will be an issue but like to ask those of you with more knowledge before I do something I'm not 100% sure about. I have fish in QT undergoing copper treatment. I have started doing small daily water changes rather than weekly or sometimes bi weekly changes on my DT. On one of my tanks I change 4 gallons a day. QT has 25 gallons of water. Is there any reason I can not treat the 4 gallons removed with copper then do daily 4 gallon water changes on the QT to help with ammonia removal rather than dumping it down the drain. Figure it will save on salt and rodi.

christwendt · Oct 15, 2022

If you are asking can you pretreat your old DT water with copper and then do a water change on QT with it, yes you can.
if you are certain your display is clean of all diseases/ parasites then you are fine. I would only do this if my main tank was stable and nothing new was added for 6 months.

vetteguy53081 · Oct 15, 2022

exnisstech said:
I don't think this will be an issue but like to ask those of you with more knowledge before I do something I'm not 100% sure about. I have fish in QT undergoing copper treatment. I have started doing small daily water changes rather than weekly or sometimes bi weekly changes on my DT. On one of my tanks I change 4 gallons a day. QT has 25 gallons of water. Is there any reason I can not treat the 4 gallons removed with copper then do daily 4 gallon water changes on the QT to help with ammonia removal rather than dumping it down the drain. Figure it will save on salt and rodi.

If and only IF you have tested amount of ammonia in QT , you can and should change the water BUT be sure to restore the copper level to therapuetic (2.25-2.5) otherwise you interupt the 30 day cycle with the copper. What test kit are you using to monitor copper level ?
If display is fishless, while you can borrow water from it- no need to change it with nothing producing waste

exnisstech · Oct 15, 2022

christwendt said:
If you are asking can you pretreat your old DT water with copper and then do a water change on QT with it, yes you can.
if you are certain your display is clean of all diseases/ parasites then you are fine. I would only do this if my main tank was stable and nothing new was added for 6 months.

vetteguy53081 said:
If and only IF you have tested amount of ammonia in QT , you can and should change the water BUT be sure to restore the copper level to therapuetic (2.25-2.5) otherwise you interupt the 30 day cycle with the copper. What test kit are you using to monitor copper level ?
If display is fishless, while you can borrow water from it- no need to change it with nothing producing waste

Display has fish but has had no new additions after all fish were treated with copper and tank ran fallow earlier this year If there is even a remote chance of this being bad I'll pass. I don't to want risk loosing fish just to save a couple bucks in salt. I have seeded sponges in the HOB and an ammonia badge in the tank. Using a Hanna tester to monitor copper daily tho using copper power it stays very consistent. I'll just mix new and use that after bringing the copper up to the correct level. I keep a brute can full of fresh mixed water so it's not difficult for me. Thanks

Jay Hemdal · Oct 15, 2022

exnisstech said:
I don't think this will be an issue but like to ask those of you with more knowledge before I do something I'm not 100% sure about. I have fish in QT undergoing copper treatment. I have started doing small daily water changes rather than weekly or sometimes bi weekly changes on my DT. On one of my tanks I change 4 gallons a day. QT has 25 gallons of water. Is there any reason I can not treat the 4 gallons removed with copper then do daily 4 gallon water changes on the QT to help with ammonia removal rather than dumping it down the drain. Figure it will save on salt and rodi.

Yes, you can do that. In fact, in the past, I've set up water re-use systems where I use water from a pristine reef to change water in a FOWLR and then use water from the FOWLR to hatch out brine shrimp.

The only issue, as mentioned is that you need to be sure that your DT has no disease issues festering in there.

Jay

MnFish1 · Oct 15, 2022

Jay Hemdal said:
Yes, you can do that. In fact, in the past, I've set up water re-use systems where I use water from a pristine reef to change water in a FOWLR and then use water from the FOWLR to hatch out brine shrimp.

The only issue, as mentioned is that you need to be sure that your DT has no disease issues festering in there.

Jay

To me this is the difficult part. 'making sure there is no disease in the DT'. Otherwise - I might suggest - and Perhaps @Jay Hemdal can comment - taking out your DT water - putting it into another tank - getting the copper level up - and leaving it for 24 hours or so - to kill any free-swimming 'stuff'. Other than that totally agree with the rest.

Rmckoy · Oct 15, 2022

Once upon a time . I had a 25 gal qt
With every fish my dt at the time going through a ich treatment . Being in Canada the only product I could find at the time was formalin .

setting up a new tank has its risks alone with ammonia so the way I went around it was to use water from the dt to change 50% of the qt water and mix new water for the dt

changed the water and dosed the qt daily

exnisstech · Oct 15, 2022

Thanks all. I don't want to risk it if there is even a remote chance of failure. I lost too many fish last time I had a disease outbreak and am trying to take every precaution to prevent it from happening again.

Rmckoy · Oct 15, 2022

exnisstech said:
Thanks all. I don't want to risk it if there is even a remote chance of failure. I lost too many fish last time I had a disease outbreak and am trying to take every precaution to prevent it from happening again.

After you start the qt
Measure ammonia daily …