How long can I keep change water in a plastic bucket? I ask because I did a water change on a 10 gal nano, all params were the same,.except the salinity was 1 point lower. I did a water change and shocked all the corals and killed one clown fish by the next morning. I am totally stumped, and quite upset. Thanks

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I heard he once packed a bong load that lasted for 8 days and 8 nights

Did you get the water to the same temp as the tank water, I do my water changes on a Saturday or Sunday, I will in most cases get my water from my RO Unit on a Tuesday and put a heater in it along with a Powerhead, the next day I will add my salt and leave it running until the Saturday/Sunday.

I only leave it 1 day heating up as I think salt breaks down easier in warmer water I can't say for sure the salt for a tank is the same I just know things like table salt or sugar melt easier in warm water so I'm guessing the salt is the same.

If everything was the same then I would start to thinking that maybe something got into the water and did it like where the water was kept did someone spray air freshner or fly killer etc etc.

I have been pondering that too. I heated the water but didn't have a power head in there, I do have an air pump to aerate it with. I let the water heat with a25w heater in a 5.gallon bucket for 2 days. Should I always mix a fresh bucket a couple days before or can I use that bucket of water for a couple of weeks?

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I heard he once packed a bong load that lasted for 8 days and 8 nights

interesting. with stuff like this it is usually something that just happened accidentally and usually it is just a one time thing, so I wouldn't worry too much about it.

Several things could have happened. a few things have already been posted. You can actually have different temperatures with your water change but you must add it very slowly so the heater can heat it up and your fish/coral will not be shocked.
Did your heater melt some plastic off the bucket? Could have introduced some bad stuff from it if it did.
The one point in salinty shouldnt do too much really. But to be safe, always add it very slowly. I'm talking about a 5 gallon change taking about 5-10 mins to get the water in the tank. Pain in the butt but safer.
Did you check for nitrates? Chlorine?
What is your water source? has it changed? I know here in salt lake, from summer to winter, they switch the water sources for some areas.
How much did you change? If you did it all, then the difference in water could have caused a major death. I have seen one person do 100% water changes on his nano but i'm sure he made sure everything was the same.
If you didnt have a powerhead in there, and you did more than a 10-20% water change, there may not have been enough oxygen in the tank water and it may have suffocated everything. But you did mention you had an airstone.
Was the bucket ever used for anything else? If so, there could have been residue from chemicals.
You should actually aerate and mix the water for at least 24 hours before adding it.
How long were the corals out of water?
Did you mix up any sand that had been in the tank for too long and not stirred up? It could have released some stuff from there. I always suggest getting a conch or something to sift and move the sand around so there arent any build-ups of SO2.
Did you notice any coral releasing anything into the water? Some coral will release toxins or poisons into the water if they're distressed. So on a small tank like that, everything could have been poisoned. This can be caused by a quick drain and refill or disturbing the corals with the siphon.
Hope some of this gives you ideas or help.

Almost all of the answers above were already helpful. Verdifer gave a good answer as well as the others.

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