Have I poisoned my fish??????

[Squirrelbuddies]

I hope someone can help me. I know it's late in some parts of the world right now....

I usually clean the tanks on Saturday AM but decided to go at it Friday night instead (and yes, I do have a life!)

My 29 gallon is setup with 20 pounds of black sand and a new fake lace rock things. The sand is not very deep. Barely deep enough for the vals to stay planted. I always remove the fake rocks so I can vac the whole bottom.

When I lifted out one of them this horribly putrid odor was everywhere. The rock has little holes in the bottom and apparently the water inside had some very bad gas (sulphur?) Some of the water poured into the tank before I realized what was going on. The tank water now smells bad -- but the whole damn kitchen does, too.

I did a 60% water change. Is that enough? Will my fish all be dead in the AM?

What else can I do? I smelled the tank after filling it and it smells better. But that smell is everywhere and attaches itself to plastic things easily so I cannot tell how the water really smells now.

I feel absolutely terrible. The rocks were specifically made for aquarium use. I also clean the tank once or twice weekly and stir the sand. So this putrid smell thing happened in less than a week....

The tank has 2 pearl gouramis and the rest are very small fish (inch or less each):

1 black molly
6 cory cats
6 black neon tetras
3 white cloud minnows

Should I put the cories in the 55 gallon with the congos and USD cats? What about the pearls? I think the other fish are too small and the congos might mistake them for food! (Although the gouramis do not seem to bother them.)

Any advice, info, etc. would be hugely appreciated!

 

[Sorrell]

I'd do a couple more large water changes. My guess would be that pockets of gas were forming under the rocks, ie the same reason we stir our sand. You won't hurt them by doing that much of a water change, but if they start acting off move them.

 

[Squirrelbuddies]

Ok. I did the 60% change at 9:00 tonight. Should I do another tomorrow morning? (10 hours later)? Or should it be even sooner than that?

 

[Tokis-Phoenix]

The smell is probably coming from under the sand; instead of the water changes i would just gravel vac/stir the sand up more often- how often do you clean your filters out and do you do them in tap water or water from water changes/dechlorinated water?

 

[Squirrelbuddies]

It was definitely the fake rock. I put it in the garage last night and picked it up this morning to give it a whiff....and OMG -- very bad smell inside that thing. I think there was an air pocket in there and the water turned very bad.

The tank smelled very good this AM (that nice smell a healthy tank has.) I did a 20% water change just to be sure and stirred the sand again. All of the fish are acting normal and look good. Water parameters are all great.

To answer your question - I do a 20% water change and bottom vac once a week. Always stir the sand and rinse the filter media in tank water only.

It was quite a scare but I think all is well now. Thanks for the replies!

 

[Sorrell]

Good to hear and I'm so excited that your fish all ended up ok

 

[Opcn]

Ill bet that some food got stuck in there or if any fish are unaccounted for an entire fish. The thing about sulfer gas is that humans are really really good at detecting it, so you can tell that there is a problem long before it hurts your fish, which is helpful, just change the water and vacume out the nastyness and your set.