help with water change

[ac]

Every time I do a water change I have fish die(within an hour of the change). I thought at first I wasn't matching the temp, but I made sure of that this time and I still lost 4 chromis. The salinity matches, I'm using RO/DI water to mix my salt. I'm using the same salt, and I let the saltwater mix for 3 days. Could it be an Oxygen problem. Should I aireate the saltwater. The fish seem to be breathing very hard before they die. Any suggestions would be appreciated.
Thanks,
Rich

 

[lovethesea]

sounds like your doing everything OK. What are you using to take the water out of the tank? Could their be soaps or detergents on there that are getting into the tank?

 

[ac]

Everything I use is devoted to saltwater. Nothing else touches the tubes or trash can I use to mix in. It's a 125 gallon tank and I changed about 15 gallons. I use an aquarium test seatest hydrometer. Fairly cheap but I've been using it for quite a long time. I figure if nothing else the salinity is consistant. I have no problems with any other tanks. Very perplexing and frustrating.:notsure:

 

[msd2]

are your water parameters all good?
My only other guess would be that something from the trash can is leeching into the tank. You might think of not letting it sit for a few days and see if that makes a difference. Plastics are very absorbant and hard to get chemicals out of once exposed, maybe at some point your can was, even before u purchased it. I would think this since you say everytime something dies.

 

[clarkiiboi]

Originally posted by AC
I let the saltwater mix for 3 days. Could it be an Oxygen problem. Should I aireate the saltwater.
I dont pre mix for days prior to adding (not a suggestion, just clarifying), so this is just a thought from reading other threads about it. I do believe you have to circulate the SW by some means. Are you doing that or is it just sitting to mix? Have you checked the parameters of the water before you add it, maybe something is off there.

 

[tony detroit]

Maybe something is up with your RO filter, even a botched up 15% water change shouldn't kill things within an hour.
Do you have a TDS meter to test your RO water?
Thanks for the kind words in the other thread.

 

[ac]

It turns out that the city has changed how much amonia they use in the processing of their water. I found out the hard way that RO/DI doesn't remove amonia. So now I'm treating my top off water and my mixed water.

 

[msd2]

Originally posted by AC
It turns out that the city has changed how much amonia they use in the processing of their water. I found out the hard way that RO/DI doesn't remove amonia. So now I'm treating my top off water and my mixed water.
Thats interesting I was under the impression that a DI unit would make water amazingly close to pure. Are you sure your DI unit is functioning correctly?

 

[ac]

I've talked to several people that agree a RO/DI won't take out amonia. One lfs sells a amonia filter that you add on to your RO unit as another stage. I'm going to look into that. The only way the di portion can remove something is if it is a positive or negative ion. So I'm assuming that the amonia is neutral in charge, and that's why it stays in the water. I'm definitely no chemist so if anyone else has some insite your input would be welcome

 

[footbag]

Get yourself a TDS meter. Ammonia should show up on that as a non 0 TDS reading. I do think that an RO/DI should remove all of the ammonia.
Do you test ammonia in your tank? Nitrates?