somethings wrong, fish dying.

[shev]

yesterday I recieved a bunch of stem plants, and floated them all at the top for a while. I took out 1/3 of my substrate and replaced it with fluorite from another tank that I was taking down. I did 40% water change yesterday to get rid of the cloudiness from the fluorite. I left the plants floating all night with the filter off so it wouldnt keep stirring up the cloudiness, I was waiting for it to settle.

I woke up this morning and found my black ghost knife dead on the ground. I looked around and found 2 buenos ares tetras dead too. the other was at the top gasping for air. and still is. my striped rapheal catfish is out of hiding and at the top gasping for air, the only ones not affected are my gouraims, that naturally breathe air, and the amount of air in the water doesnt affect them. my african knife fish seems alight, but he can breathe air too if he wants to. my african butterfly fish is fine because he also can breathe air.

so what happened? I didnt disinfect the plants, just rinsed them off. they could have carried something nasty over to my tank. this is a stretch, but I did add the plants at night, so they were using the dark reaction, and used air instead of co2, maybe that took all of the oxygen in the water? turning off the filter didnt cause it since Ive done that before, but it didnt help. the substrate was in a tank that didnt have any fish in it for a week. maybe the helpful bacteria died? that'd also remove allot of oxygen.

looking at the dead fish, all I see wrong is loss of color, and frayed fins. no bloating, their eyes arent even glossed over yet. Ive removed the plants and turned on the filter, dont know what else to do. any help appreciated.

[Baby_Baby]

I don't know too much about what happend. that is very sad. I'm sorry about your fish.

[shev]

well.... everybody seems to be ok now. before they were all gasping for air. I wish I had woken up earlier. Since everyone is doing better I think its not a disease of some kind.

[drosera]

Hi,

I'm very sorry about what happened. I can't give you a definite reason for why your fish died, but I can offer some ideas of what might have happened.

From your description, it seems fairly certain to me that whatever killed the fish disrupted their breathing somehow. But the effect seems to have been short-lived. IMO, it was definitely not a disease. I don't think any spills or introduced toxins would have done this either, since again, the rest of the fish seem to be doing well.

CO2 seems a possibility, though I'm not totally convinced. I doubt the night cycle of your plants would have caused that much problem. I could be wrong.

Another possibility, and the strongest one in my mind, is that the plants and/or substrate contained either noxious bacteria, or gases from them ( in the case of the substrate.) As you stated the fluorite was from another tank. Was that tank still running? The plants as well may have had dead/bad bacteria on them. It sounded like you might have received them through the mail? If so, the lack of light and Oxygen could very well have tainted the plants. I've had this happen to me bad enough the plants wouldn't recover. And don't forget. It's not just about the good bacteria dying. It's also about the bad ones (usually anaerobes) taking over in their place too.

If I were you, I would do significant water changes for the next few days, and most importantly, keep the water well filtered and aerated. The plants should be moved to another tank (filtered and aerated as well), until they seem to be growing healthily. I'm sure some people here would recommend a complete breakdown and cleaning of the tank, but I'm not sure about this one way or the other.

I personally would also increase light levels or times. This of course would bring on algae problems, but to me this is preferable. The algae and microbes associated with it would compete with the bacteria, and in that way cleanse the tank to some degree. Others would say the plants are enough for that.

At this point, the best thing is to make sure the fish remaining don't suffer any more stresses. Keep them calm, properly fed, clean, etc.

Hope that helps. Good luck!

Chris

[Damon]

I was leaning toward hydrogen sulfide also, but its not likely since the substrate was transferred, thus no longer inert. I would lead towar CO2 poisoning or better yet lack of O2 (they are not linked).

[shev]

the fluorite was in a 20 gallon with no fish in it. I didnt run the filter or the heater since there werent any fish, the bacteria may have died. I also had MTS int he fluorite, i figured it'd supply some amonia to the bacteria in the tank. sine I rinsed the substrate I may have killed some mts, dead snails in the substrate would suck some oxygen out too.

so it is plausable that the plants sucked out the oxygen?

all the fish seem back to normal. thanks for the help.

[TheOldSalt]

1-- you added a whole lot of plants. Didn't you say you got 100 stems from an auction?
2-- You changed 40% of the water
3-- you turned off the filter
4-- you disrupted the substrate
5-- you left things in the dark after all this

Adding a bunch of plants suddenly will of course be disruptive to the system. Changing 40% of the water will lower the O2 since the water isn't well aerated when raw from the pipes. Plants consume oxygen and produce CO2 in the dark, and to exacerbate the situation, you turned the pumps off so they couldn't correct the gas saturation balance.
The disruption of the substrate was probably the least of the problem if it contributed at all.
Some sort of poisoning doesn't seem to be the case since only the gill-breathers were affected and everything is fine now, so I'd have to say that suffocation is the most likely suspect.

Doing any of the things you did would, on their own, not be a problem. However, you did them all at once, and that was just too much.

[shev]

yeah, huge noob mistake on my part
I got the plants and decided I needed to put the fluorite in. it was cloudy so I did a water change. still cloudy so i turned off my filter to let it settle. didnt want the plants to dry out so I stuck them all in and went to bed. I feel horrible now, in hindsight it seems kinda obvious.

-- you added a whole lot of plants. Didn't you say you got 100 stems from an auction?

I actually got 500 stems. $6 I couldn't resist.

Ive got all 500 stems in a 20 gallon (no fish in there), its completely filled. should I start to gradually put them back in my 55 gallon?

I currently have overkill on my aerating.

[maxpayne_lhp]

Oh... sorry about your loss! It was terrible. Good that everything's better now. So that was mainly because of the sudden add of plants?

[TheOldSalt]

500 plants in a dark 20 gallon tank. YIKES!
Well, mystery solved, at least.

Yes, by all means, start distributing them to other tanks.