All of our fish are dead...Advice needed please

darrenkarp

Reefing newb
Hi all,

As this is my first post on this forum I think a little background information on me is needed.

I used to keep marine fish in a large tank (some 6ft x 4ft x 3ft) about 7 years ago without any problems whatsoever. We sold the tank as it was costing a fortune in running costs and we needed more space in our living room.

My daughter (13) is fascinated with marine fish and for her birthday in September of this year we bought her an Aqua One Aquamaine 900 tank complete with Marisys 240 filtration system. I set the tank up with coral sand, RO water, and about 60 kgs of excellent living rock from a fellow enthusiast. I let the tank cycle for around 3 weeks before adding our first 2 fish - a pair of mated percula clowns, the female was huge!

Two weeks later we then added a small spotted grunt and a yellow tang.

Everything was fine, the fish were happy and eating very well. I did weekly 10% water changes and tested the water for, Ammonia, Nitrite, Nitrate, Phosphates (I use a small bag of Rowaphos in the filter), pH and salinity. My water was great with only a slight under 10ppm of Nitrate.

On friday my daughter called me at the office to tell me the female clown was dead and she couldn't find the spotted grunt. I raced home to find the yellow tang panting on the floor of the tank. I tested the water and found Nitrates were at 20ppm and performed an emergency 20% water change. All other water tests were fine.

No sign of the spotted grunt and my daughter couldn't remember the last time she saw him, so he must have a died a few days beforehand. The next fish to die that evening was the yellow tang. We only had one fish left now, the male clown. He died this morning.

Yesterday I took a sample of my water to my local shop and he said the water was fine and put down the deaths to a lack of oxygen in the water. He said to increase the water movement at the surface which I did by angling my Tunze upwards, creating a large amount of water movement. The male clown still died 24 hours later.

Now all we have left is a load of clean up crew and a cleaner shrimp and my daughter is devastated, as am I.

I obviously don't want to add another fish until the cause of such sudden deaths has been found.

What can I do guys?

TIA
Darren
 
Did something spill into the tank of did you do some ceaning in the room like glass cleaner or Pledge or something? What about metals, did you test for copper or anything like that? Are there any spots on the fish or anything like that? If you think the water is ok you can add a Green Chromis, they are very hardy. Also, what about your water temperature, any swings there? Perhaps an open window in the cool air?

If you had a lack of oxygen the fish would've been "gasping" for air at the surface, did they do that?

Oh, and welcome to Living Reefs, it's good to have you! Their are many peeps here that will help you!
 
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Well, coppper was not the culprit, so don't bother testing for that. Copper would not have affected the fish, but it would have killed your inverts.

What size is the tank?
 
Did something spill into the tank of did you do some ceaning in the room like glass cleaner or Pledge or something? What about metals, did you test for copper or anything like that? Are there any spots on the fish or anything like that? If you think the water is ok you can add a Green Chromis, they are very hardy. Also, what about your water temperature, any swings there? Perhaps an open window in the cool air?

If you had a lack of oxygen the fish would've been "gasping" for air at the surface, did they do that?

Oh, and welcome to Living Reefs, it's good to have you! Their are many peeps here that will help you!

No polish was used near the tank. The water temperature was 72 - 74 degrees but obviously the emergency 20% water changed would have dropped that. The yellow tang was panting at the base of the tank. No fish have ever been seen doing that at the surface.
 
Sounds like it was an oxygen problem to me as well. I would do weekly water changes and wait 6-8 weeks before adding anything else. Also make sure you don't over populate your tank. I would limit your fish to 2-3 and no Tangs in that small of a tank. Good luck and welcome to the forum.
 
Sounds like it was an oxygen problem to me as well. I would do weekly water changes and wait 6-8 weeks before adding anything else. Also make sure you don't over populate your tank. I would limit your fish to 2-3 and no Tangs in that small of a tank. Good luck and welcome to the forum.

Thanks for the replies everyone.

Is there a way of testing to ensure it was an Oxygen based problem. The store where we bought the tank had about 150 pounds of LR and loads of corals, anenmoes and about 8 fish. Is 2 - 3 fish all that we can fit in...it's really not that small.
 
Did you cycle the tank? Also a tang does not need to be in a 40 gallon tank. Too small of a tank will speed up disease and illness in fish. Pointing a PH up to the surface will increase aeration if that is what the problem was. Just some observations.
 
Did you cycle the tank? Also a tang does not need to be in a 40 gallon tank. Too small of a tank will speed up disease and illness in fish. Pointing a PH up to the surface will increase aeration if that is what the problem was. Just some observations.

Yes, tank was well cycled.
 
Sorry guys if my replies aren't more complete. My daughter and I are so pissed off and concerned that we've contributed to the problem
 
I'd think that low oxygen would have effected the inverts to,but dont hold me to that.
Have you checked for stray voltage?
OH
Welcome to the site.
 
It could be disease too. The tang being stressed might have made it susceptible, it served as a breeding ground for the organism, and it spread to the other fish. With a high bioload, just like in a crowded apt, stuff can spread more quickly.
 
YOu can add live rock and corals, they don't count as fish that I know of. Like Biff said, what is your set up? Do you have power heads, live rock, etc?
 
Brooklynella looks like a very likely cause.
Hi, pictures I've seen of a clownfish infected with Brooklynella look remarkably similar to what I saw on Friday morning on the female clown. We bought the pair of mated clowns 4 weeks ago and they were in the tank by themselves (apart from some cleanup crew which were there about 10-days before the fish). We then introduced the tang, spotted grunt and a cleaner shrimp two weeks after the clowns.

Does anyone know if it was Brooklynella:

1. How long the infection takes to manifest itself (so I can draw a conclusion as to which fish(s) had it.
2. Now with no fish in the tank, just cleanup crew and a shrimp, how long to wait for the infection to pass before introducing more fish.

TIA
Darren
 
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