How to Set Up a Quarantine / Hospital Tank for Koi and Goldfish
Now that we’ve drilled into you the value of quarantining and treating newly acquired koi and goldfish before introducing them into your existing (and much loved) population let’s explore some quarantine tank designs and how to set one up so that it doesn’t work you to death during the two to three weeks it is occupied.
There are many ways to set up a quarantine tank. It can be done as a temporary unit that can be re-assembled as needed or as a permanent fixture. The best thing about it is that it will serve double duty for you by providing a hospital tank should the need ever arise.
Requirements
The quarantine tank is a temporary home for the new fish and should have all the amenities of the larger and permanent pond – it just doesn’t have to be as elaborate.
- It MUST be aerated 24/7! You will need a pump and fountain or aeration device.
- The tank has to be large enough for the fish to swim easily without stress.
- You must be able to net the fish easily.
- It needs to be located near the water source or have a hose nearby for quick water changes.
- It must be covered. New fish jump!
- Do not place it in full sun.
- You may need to heat the water if the water temperature is lower than 72 degrees.
The Tank
You can use basically anything that is NOT made of metal that holds water for a
quarantine tank. Aquariums, plastic tubs, baby pools, horse and cattle watering
troughs – all have been used quite successfully – and all can be dismantled and
stored away until needed again.
You can also construct your own using railroad ties or concrete blocks with liner. This kind of set up tends to be permanent and is not easily dismantled.
The best design for a tank comes up to about the waist for your comfort as well as the fish’s. Koi and goldfish tend to be more at ease and sociable when we’re not towering above them and that insures a less stressed environment. Plus it is easier for us to administer treatments and net the fish when necessary.
The size of the tank depends on the number and size of the fish that you will be treating. You could easily use a 10-gallon aquarium for small tropical fish but that 10-gallon aquarium will not work for most koi and goldfish. Both fish, especially koi, are bulkier and give off much more waste than tropical fish that are tiny in comparison.
We suggest going with no less than 50 gallons for one or two very small koi or goldfish. Most people, however, tend to purchase koi and goldfish that need a little more room than that. We prefer to use large heavy-duty watering troughs available at any feed store. They come in 50, 100, 150 and 300-gallon sizes. Most people would do well with the 150-gallon size but others with larger koi should invest in the 300-gallon size.
We don’t suggest anything much larger than 300 gallons because it becomes harder to catch the fish and costs more to treat it.
Where you place your tank can literally mean the difference between life and death. If the tank is in the sun the water can get too hot for the fish to tolerate and the warmer the water the less it holds oxygen. Place the tank in a shady location outside, inside the garage or basement or in some sort of sheltered area.
Water changes are a necessity when treating and holding fish in a quarantine tank so, for your own convenience, have the water source nearby. Unless you build yourself a permanent tank equipped with an active biological filter you will experience ammonia and nitrite spikes. The water will have to be changed often. Water changes are also necessary between treatments. Keep plenty of de-chlorinator (we suggest Ultimate Water Treatment) handy if not using well water.
Don’t forget to factor in where the water will go when you drain the tank. If the tank is inside the house or garage a simple long hose attached to a pump will work wonderfully to guide the water out and to the area where you want it to go.
Cover the quarantine tank! We have lost many a fish during the quarantine period from not keeping it covered. New fish jump constantly until they get accustomed to their new home. Parasites, water problems and treatments will encourage them to jump as well. A net can be used but be sure that it is pulled taunt against the edges and no pockets are present that can catch the fish and keep it suspended outside the water. Plywood can be used as long as it is weighted down and a small portion left open where gases can escape. The Doc once used my window screens which worked well for him (weighted down) but once I started wondering where my screens were going off to he had to choose between the screens or me and I’m happy to report that he did not choose the screens.
You may or may not need a heater for your tank. It mostly depends on what time of year it is. One of the reasons we quarantine our fish before adding them to our established ponds is that a fish could have a virus that can kill the whole population. Some of these viruses only appear when the water heats up. You could put your new fish through the proper quarantine and treatments and still end up killing all your old fish if the new fish has never been exposed to water temperatures higher than 72 degrees. If the water temperatures are less than 72 degrees you need to heat the tank so that any virus lying in wait will manifest itself while in the quarantine tank.
If you are using your tank as a Hospital tank and feeding the koi or goldfish medicated foods those antibiotics will not work unless the water is above at least 68 degrees. A heater would be needed then also if treating the fish during winter or when the water temperatures are low.
Aerating the Tank
Aerating the quarantine or hospital tank is not an option. If you think you can get by without it you will end up with dead koi or goldfish. It’s a matter of time. Koi and goldfish simply cannot survive in water deprived of dissolved oxygen. Depending on the water temperature they can suffocate within hours or days. The aeration must stay on all the time. Do not place it on a timer.
There are basically two ways to aerate the tank. Each way requires a piece of equipment. You can use a pump with a fountain or hose or you can use an aerator kit.
At the water garden center in Alpharetta the majority of our quarantine tanks were aerated using a submersible PondMaster Pump/Filter/Fountain combination. This handy item is insanely simple to install and relatively inexpensive, costing only about $150 for a pump, filter and fountain. A rock must be placed on it, however, to keep it from floating up, especially when new. When you need to drain the tank you can slip a flexible hose over the fountain end of the pump and allow the pump to drain the water from the tank.
You can also use a pump and hose to aerate your quarantine tank. Simply wind the hose around so that it dumps (with as much bubbles as possible) right back into the tank. This is not the most desirable set up because it doesn’t produce as much aeration as the fountain so we would strongly advise purchasing a fountain kit instead.
An aeration kit is another option for aerating your quarantine or hospital tank. It consists of an air pump, air hose and air stone. A small, dinky aeration pump meant for an aquarium will not do the trick. You need one that is sized correctly to the size of your tank. You must also be careful to purchase one that is rated for outdoor use if your quarantine tank is outdoors. Those tend to be a bit more expensive and you won’t generally find them at pet supply stores. You will need a separate pump and hose for draining the tank.
Filtering the Quarantine Tank
Temporary quarantine tanks do not need a biological filter because there is simply not enough time to build the proper nitrifying bacteria – and it’s just a waste of money. Water testing and changes are very much a part of the quarantine process. In permanent tank situations, however, many choose to install biological filters to insure healthy water parameters during the treatment process and to cut down on the number of necessary water changes.
It’s very important that you choose a biological filter that has a by-pass feature or is set up with a by-pass. Often, especially in hospital tanks, we must treat the koi and goldfish with bacterial treatments that will kill the nitrifying bacteria that we fight so hard to keep in our biological filtration.
The Mac-Daddy of Quarantine Tanks
For you serious koi-keepers out there who want to build yourself a low-maintenance, permanent quarantine tank solution we have just the article for you! Click HERE to read it.
Items You May Need
