Old tank syndrome?

I know there is such a thing as new tank syndrome but I'm wondering if there is such a thing as old tank syndrome. I'm asking because my mom's 29 gal. has become this tank of doom basically. It's been set up over 13 years (with same rocks, new filters were added last year and new heater this year) but within the last two years everything that goes in the tank is dying. The most recent victims are two CAEs and two panda cories. They were also the most recent fish added. Right now the stock is at: 5 gold tetras, 1 rummy nose, 1 cardinal, 3 black skirts, 28 guppy fry, 2 CAEs, 1 female betta.

Now, since the fish are mysteriously dying off one by one with no sign of disease we took some water to the lfs for testing since we dropped over $25 on fish this last weekend and about $15 a month ago and nothing lives. Ammonia was at 0, nitrite, 0, nitrate, 25 (i think). We basically stumped the whole staff of the lfs (who are usually quite knowledgeable). They admitted there was absolutely nothing wrong with our water and there was no reason for our fish to die. But of course since our 24 hr gaurantee had expired a week past they didn't offer to do anything for us either. We just left the store confused as to why the fish are all dying.

So, the only thing we can think of is basically tearing the tank down and starting all over with new rocks and filter cartriges and possible a new light as the light is getting kinda dim. Does anyone have any suggestions? Are the fish suffering because the tank is old? Could there be some other problem? And before anyone asks, the cories came from the lfs and the CAEs from wal mart so I don't think it is a store problem.

Thank you,

 

Anybody? I'd love to hear from anyone with an opinion or experience. Please I'm begging here, we lost another CAE last night.

Thanks.

 

I have kept fish for over ten years and have not heard of "Old Tank Syndrome" however that dosen't mean there isn't such a thing!?! It sounds to me that your tank is overrun by disease. If I were you I would do an "emergency cleaning" on your tank. First if you have any remaining fish they should be put in a hospital tank. I would throw out the rocks/gravel and replace it with new stuff since it is difficult to be sure it is all cleaned and rinced propperly. Any live plants should be disposed of as well as any airstones (replace these items with new). Empty the aquarium of all water. Clean all of your decorations with bleach and water as well as the tank. You must be very carefull to rinse everything really well after using the bleach. DO NOT use any other household cleaners. Normally you would not want to change all filter media at once but in this case I would because basically you are going to start fresh salvaging what you can. Don't forget to bleach and rinse the inside of the actual filter well. Lots of work but it sounds like you don't have a choice. Just make absolutely sure to rinse all the bleach off of everything. Then rebuild the aquarium as you did when you first got it remembering not to add fish again untill the tank has cycled. :shock:

 

Hmmm... disease you say... not what I wanted to hear. I did find one article that explains an old tank syndrome. It basically says that once an aquarium is established (ie cycled) and the stock is added and the aquarium continues to be disease free the owners become complacent about the tank because they haven't had any problems. The tank goes longer without water changes and so the chemistry changes. Eventually these changes kill of more delicate fish slowly until only the very hardy ones are left. The owner assumes these fish were just old as they'd had them a very long time. Well since there is now free space in the tank the owner goes to add more fish only to have them mysteriously die without any sign of disease because they can't adapt to the radical conditions that are now present in the tank.

This seems to fit exactly what has happened with our tank. My mom got the tank as a valentine's gift when I was nine and my sister 14. She never had a whole lot of time to perform the maintenance as we were growing up and once the aquarium had inhabitants living happily we didn't pay as much attention to it as we should have. Which is how we ended up in this situation according to the article. I will post the article here now for others to read, I believe it was taken from Tom Griffins web site. Moderators: if it is not ok to post articles please feel free to remove this as I don't want to upset the author.

Thanks for sharing ceverettes but I'm leaning toward this theory now. Anyone else who has opinions on this article or my situation please feel free to comment.

Thank you!

Edited by Hooben, it was just to long of a thread and was not written by you. Thanks

 

I suggest buying your own test kits so you can check the water yourself (personally, I don't trust most LFS employees). If maintenance hasn't been that good on the tank, then it is possible that the parameters are out of whack and that's what's killing the fish.

-Chelle

 

Thanks guys! And Hooben, I wasn't sure if it was ok or not, thank you for the correction.