Hospital Tank

[MuchThug]

I have an established 5 gal tank that is being used as a hospital tank due to an upgrade, there are currently no fish in there but i was wondering will the tank uncycle if there is nothing in there? Should i still feed the tank?
Thanks

 

[eaglesaquarium]

Yes, the bacteria will eventually go dormant if there is nothing in there. 
 
There are several ways to go about fixing this problem.
 
1 - Dose a little ammonia every few days.  Twice a week adding the 'snack dose' as directed in the cycling article (see link at the header)... this will of course lead to nitrates sky rocketing (as you normally wouldn't be holding a cycle in a pattern like this indefinitely), and so you would need to do water changes on the tank fairly frequently to remove them... likely every 2 or 3 months (and definitely want to do a 100% water change before adding a sick fish).
 
 
2 - Depending on the filter set-up in your main tank, you can add the filter media from your QT to the main filter and keep it cycled that way.  It may or may not have enough bacteria for the QT when you need it, but it will definitely hold some and can kick start what you need in the hospital tank.
 
 
3 - Move extra filter media over from your main tank into the QT to deal with the extra ammonia.
 
 
 
Personally, I wouldn't be running an empty tank just in case I have an issue.  But, it is a great thing to have a QT available when needed with all the relevant parts.  The good news is that they can be REALLY fast to set-up if you have all the pieces.
 
1 - You can just use water from the main tank to fill the QT, or about a 50-50 split with fresh tap.  This means that your fish will be immediately (or almost immediately) acclimated to the QT, as its the exact same water and the exact same temp.  You can place the heater in the tank to maintain the temp - or to bump up or lower the temp as necessary for your particular ailment.  
 
2 - Once the water is in place, and the fish, the filter can be set-up using the spare media in your main tank, or anything else.
 
3 - Add some floating plants from the main tank, if you have any, like anacharis, etc. as this will give the fish a little cover and give them a stronger sense of security.  
 
4 - Keep the tank in the dark.  Dark tanks are better for the fish than bright lights when already being stressed by disease and isolation.

 

[TwoTankAmin]

In 15 years of keeping fish in multiple tanks I have never used a cycled Hospital tank. I see it as a waste of good equipment and decor and especially of cycled media. Here are the reasons why:
 
1. Fish stay in an H tank for a short time. If fish are sick enough to need an H tank, either things will improve fairly fast or else they go the other way.
2. Many meds can kill off the bacteria. How would you know they are gone? Many meds discolor the water which makes getting good test results difficult to impossible.
3. If one fails to diagnose for sure what the cause of the problem is and the fish do not make it out of the H tank alive, then one has no idea what pathogens/parasites/etc. may be responsible which means everything in the H tank will need to be sterilized before it might be reused. This will kill the good bacteria. it also may kill any live plants one puts in. It is difficult to sterilize wood.
4. Water changes are likely to be done several times a week. These replace the need for a cycled tank to handle ammonia.
5. There tends to be a decent amount of bacteria in/on one's substrate, but H tanks should be bare bottom.
 
Here is how I set up and manage an H tank.
 
1. Equipment is as follows: heater, airstone(s) with pump, thermometer.
2. Decor as follows: plastic plants and hard type rocks (they don't absorb). This decor helps reduce stress levels by providing cover and can be sterilized for reuse.
3. I use new clean water. The potential cause of the problem may actually be in the main tank water. This would mean the main tank would need meds (a different discussion). But until I know this for sure, it makes more smuch current while still getting plenty of O.
5. The smallest tank I use is a 10 gal. (38L). If it is more than is needed, I do not have to fill it all the way. Meds are expensive, so the fewest gallons I have to medicate, the more affordable it becomes. If one has bigger fish, a larger tank may be needed.
 
An H tank serves a different purpose than a Q tank. The latter may end up morphing into an H tank, but until it does, it would remain med free. I also Q fish for between 4 and 13 weeks depending on the specific situation. So I start by having it be a cycled tank. However, I am also prepared to throw out the filter media, any live plants and any needed wood (based on fish species involved) etc. if things go horribly wrong and it becomes an H tank.
 
This is just my way of doing things and does not mean there are not other ways. I tend to have more tanks than the average hobbyists and have more fish coming and going as a result. I also have the excess equipment that gives me the flexibility to do things in a variety of ways.

 

[Ace_Of_Fades]

TwoTankAmin, that was some really helpful info on hospital tanks, you should do a write up on hospital tanks and sticky it somewhere.