Why would this happen!!!!

[rdefino]

I have a 75gal FOWLR and I use RODI water and when I do a water change (15gal) the fish seem to be breathing very hard after the water change. I mix the water for a few days before using it. Any idea what can cause this?

Thanks

 

[Hara]

are temperature, salinity, ph as close as possible to the original tank water? Is it thoroughly oxygenated beforehands (not sitting stagnant in a bucket)?

 

[rdefino]

The temp and salinity are right on. As for the PH I didn't check. If it is not the same, how do I get it to be the same? Any idea what else can cause it?

Thanks

 

[Phyl]

O2 sounds like a very likely culprit. Do you continue to mix/aerate the water after dissolving the salt? We keep our water circulating with surface disturbance until we do the water change.

 

[Kam]

Try something simple like putting an air stone on an air pump in the water. That should saturate the water with O2.

 

[rdefino]

I was told before that bubbles in the tank were not good, so how can bubbles in the water buckets be good?

 

[Phyl]

Bubbles in your display are distracting and annoying (but not *bad* for anything). The good of them is that they promote gas exchange and oxegenation of the water. There are good reasons for bubbles (there are lots of them in my sump, I just try to keep them out of my main!). So they're good in your mixing bucket for sure! I just point my powerhead at the surface of the water and that keeps it aerated.

 

[jackdp]

I'm only mixing 3-5 gallons of saltwater at a time, but I use a powerhead hung over the side of a 5 gallon bucket. I use a piece of air tubing connected to the air inlet on the powerhead to keep the bucket well aerated. If your letting it sit stagnant the pH could also be somewhat low. Best to measure parameters of your newly mixed SW now and then to be sure its in good shape.

 

[Edmonton Eskimo]

I really doubt that it is an oxygen issue. If you are doing a 15 gal water change in a 75 gal tank even if the oxygen was low it is only 15 gals of water. Your oxygen levels would have to be low in your main tank to begin with in order for this to be an issue

 

[rdefino]

How can I determine if my oxygen is low in the main tank?