Jump to content

How long can a tank stay cycled without fish?


Recommended Posts

  • Regular Member

Ever since my last goldfish that was in my 40B tank died, I just let it run empty unable to bring myself to take the tank down, or to get any new fish during that time. I finally went and got new goldfish and is in day 5 of the quarantine/Prazi rounds in the 10 gal Q tank. Then it dawned on me that I didn't think to even check to see if the 40B tank was still cycled so I tested the water, it said 0 Ammonia, 0 Nitrites, and Nitrate 40. I did a 50% water change and tested again. It read 0 Ammonia, 0 Nitrites, and it looks like either 10 or 20 Nitrates, It kind of looks more like 10 maybe? (Couldn't figure out the difference in shades between 10 or 20 very well). So is the 40B still cycled, or what? If it is, how long will it stay cycled before the new Goldfish are ready to go in after their Quarantine/Prazi time is over? How do I keep the cycle going until the fish are ready to go in it ? 

Link to comment
Share on other sites

  • Regular Member

I honestly would not put new fish into a tank where previous fish have died like that. I would sterilize the tank and start the cycle over with pure ammonia. Even if the tank has been running empty - if the beneficial bacteria could survive, so could all kinds of other horrors. If I DID decide to put them in that tank - I would treat them for parasites AFTER I put them in, not before.

Depending on how long you've let the tank sit already - you likely don't need to do much else to keep the cycle going. Clearly there's some type of contaminant or something that the beneficial bacteria have been able to feed off of.

Link to comment
Share on other sites

  • Regular Member
22 hours ago, mjfromga said:

I honestly would not put new fish into a tank where previous fish have died like that. I would sterilize the tank and start the cycle over with pure ammonia. Even if the tank has been running empty - if the beneficial bacteria could survive, so could all kinds of other horrors. If I DID decide to put them in that tank - I would treat them for parasites AFTER I put them in, not before.

Depending on how long you've let the tank sit already - you likely don't need to do much else to keep the cycle going. Clearly there's some type of contaminant or something that the beneficial bacteria have been able to feed off of.

Thanks for your answer, I appreciate it. :thanks My previous goldfish had started to get giant tumors all over his body that was making it difficult to swim very much any more and I had to hand feed him for a couple of days when he could no longer get up off the sand very well on the bottom, but he still had a big appetite. I was thinking of having to put him to sleep, but then he passed away a couple of days later. He didn't seem sick otherwise, that's why I thought I could just re-use the tank for the new fish. I could add Prazi to the 40B too, that would be a good idea. 

The 40B has been running empty since December 17, 2020, so a little bit over a year so far. I was only adding water when it was getting an inch low, and doing water changes like once or twice a month during that time, so I'm not sure what the bacteria is living off of really if the cycle is still going after a year. :hummm

Link to comment
Share on other sites

  • Regular Member

Oh wow - yeah running empty for a year. Yeah I definitely would start over. You COULD rinse and keep the media if you wanted to. But I would definitely drain, empty, and properly clean and scrub the tank and everything before I put a new fish in there.

I have a 3/4 year old fish who I noticed has a tumor on his face. This is common in goldfish - and even MORE common in red/orange pigmented areas or totally red/orange pigmented fish.

Can't wait to see the new fish!!

Link to comment
Share on other sites

  • Regular Member

Your original readings are your tank are based on the level of beneficial bacteria in your tank. Adding a goldfish adds a tremendous amount of waste to a system that if not fully cycled will cause you to have water problems.  There is probably not enough beneficial bacteria in your system to handle a goldfish at this time. I would do as instructed. Empty the tank, fill with clean fresh water and use prime as your conditioner. I would keep the same filter material that you have been using because there are some beneficial bacteria in the filter. Decide if you are going to do a fish less cycle or cycle with fish. Please describe what type of filter you are using, how often you change the water when you have fish, the type of food you feed, and how many types of fish you plan on adding. Good luck

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Restore formatting

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

×
×
  • Create New...