Water change error - I think anyway.

[newby01]

So, I have had my salt water fish only tank set up now for about 6 months. Been progressing well, no real issues. I decided to complete a large water change yesterday. Huge error on my part, I changed out about 80% of the water. (Yes, I understand now this was incorrect.)

I haven't lost any fish, but they are acting like they're possessed. Darting around the tank, hitting the glass, hitting the bottom. It's very odd. Fish consist of:
1x fox face.
1x blue damsel.
1x niger trigger.
1x red fin fairy wrasse.

I also have a zebra moray eel and he seems fine.

I don't have any corals.

I think I may have given the fish osmotic shock? Any idea how long this lasts or are they all goners?

Thanks in advance.

 

[Sharkbait19]

80% is a large amount. Did you test your salinity before/after? If it changed drastically than that can definitely put a negative impact on the fish.

 

[Sebastiancrab]

What everyone needs to know are what are you sourcing for water? And what are all your water parameters - ammonia, nitrate etc? Why did you do the water change?

 

[newby01]

Salinity went from 1.025 to 1.027. (Using a refractometer)

I had to re-bed under-gravel filter under the sand and don't have enough storage for all the water, hence the large change, everything came out and went back in.

Tap water but added marine buffer, seachem prime and marine carbonate to help treat the water.

 

[KrisReef]

Tap water is good for drinking but can carry minerals and ions that stress the fish. Are the fish breathing fast? If yes, you might want to increase oxygenation in the water by aiming a powerhead (if you have one) towards the surface, or the return water from filtration, use either to disrupt the water surface.

Do you have live rock in the tank or just an undergravel filter with sand for filtration?

 

[newby01]

Yes there is a significant amount of live rock in the tank.

I do have two power heads in the tank and will do that right away. I also have a bubbler in the tank and the top seems to be agitated. The tank has had the same surface agitation for the same 6 months and no issues??

 

[mdb_talon]

Tap water but added marine buffer, seachem prime and marine carbonate to help treat the water.

So you used tapwater, salt mix, marine buffer, and marine carbonate? How high exactly did you want your alkalinity and PH?

If anything using tapwater means you dont want to use any buffers.

 

[newby01]

I just wanted to ensure that everything was in there as per before. And before, the water had those items, so I made sure I reintroduced them.

 

[mdb_talon]

I just wanted to ensure that everything was in there as per before. And before, the water had those items, so I made sure I reintroduced them.

Of the many things in tapwater many of them would be "buffers". Saltwater mixed to the right salinity is all you need to use when changing water unless you are trying to match specific alkalinity/etc then you may need to dose something. That should not be done without knowing what the value you are at and the value you want. I would guess your alk(and probably PH are very high)

 

[jaganshi066]

1.027 might be a little hard on the fish, especially if they aren’t used to it. I think it would have been easier to go from 1.025 to like 1.023/1.024 but I heard going up isn’t good

 

[Acros]

Do you have to stir up the sand bed to work on your under gravel filters? I don’t know how they work. Kicking up the sand bed usually could cause an ammonia spike in a reef tank.

 

[Sebastiancrab]

I agree with James. Chances are your ammonia may have spiked too. Good idea to have the Prime but I would watch things carefully. I am not familiar with how all these things might interact. Sounds like a lot to throw in at one time. It might not be a bad idea to get some RODI saltwater from your LFS and change some more of your water out. I also suggest you invest in an RODI unit in the future. It will pay for itself.

 

[mehaffydr]

If you did not have adequate storage did you mix the salt and then immediately add it to the tank. You really need to mix the salt and let that mix for minimum 24 hours before adding to tank with fish

 

[mdb_talon]

If you did not have adequate storage did you mix the salt and then immediately add it to the tank. You really need to mix the salt and let that mix for minimum 24 hours before adding to tank with fish

I agree it needs to be properly mixed, but the 24 hour minimum is not accurate. Red sea for example says mix for 2 hours and to use within 12 hours due to precipitation.

 

[mehaffydr]

I agree it needs to be properly mixed, but the 24 hour minimum is not accurate. Red sea for example says mix for 2 hours and to use within 12 hours due to precipitation.

True I have just always errored with caution to be sure its mixed and proper temp. But without a holding tank I suspect the OP may have added just mixed saltwater?

 

[newby01]

Ended up losing everything except the Wrasse. Kind of crappy but I've learned a valuable lesson here. Opportunity for me to start fresh I guess.

 

[count krunk]

The replacement water was too different in salinity and likely ph and alkalinity. It stressed the fish out enough to start a chain reaction.

Stress in fish is almost always the first domino to fall that leads to the fish dying.

 

[Lost in the Sauce]

I'm very sorry to hear that. what is the lesson you learned? Was it the sand bed causing ammonia spike? Salinity spike? Giving a detailed after action of what you found may help others in the future to not make the same mistake.

 

[Rmckoy]

Before pointing at any of the possible issues .
adding buffer and carbonate will only raise alk .

a full test of all parameters will help .
A large water change isn’t always bad if parameters are matched .
Temp , salinity , alk etc .
have you tested since the water change ?

 

[Rmckoy]

The valuable lesson should be .

never add anything or dose anything that you haven’t tested the need for .