Hints & Tips
Helpful tips on discus fish
Feeding recommendations
The discussion about feeding discus fish has been extensive and differing opinions presented. We feed the fish in our breeding operation exclusively on our STENDKER discus feed which we have adapted to the needs of discus fish. This is a good, balanced feed which helps the discus fish to remain healthy, develop rich colouring and grow strong. We recommend given our STENDKER discus feed 3 x daily to your fish.
Our STENDKER discus frozen feed is available as 30 g sausages, 100 g blister packs and 500 g flat blocks.
The required amount of food can be cut off from the frozen 500 g block in the right sized portions using secateurs. You can keep the thawed feed in the fridge for two days (see also "Food and feeding discus fish").
Sizes of discus fish groups
Discus fish live in shoals and therefore should always be kept in a group of at least 10 - 12 fish. We strongly recommend adhering to this number, otherwise one fish will be excluded from the group and will not get enough to eat.
Selecting discus fish
You should decide in advance which type of discus fish you want to keep since fish from different breeding operations have different microbial strains and therefore may not be mixed. Discus fish are sold in pet shops as fish caught in the wild, from Asiatic breeding operations or as our STENDKER discus fish (made in Germany). (See also "Population density and companion fish in a discus aquarium“)
Sleeping and waking rhythm of discus fish
The optimum conditions for your discus fish are for the lighting to be switched on and off at the same time each day (can be set on a timer). It is also important to feed them at the same time. The optimum is to feed them in the morning one hour after switching on the light, with a second meal at midday and a third meal two hours before the light is switched off at night. The fish will get used to these feeding times and will soon be waiting for you at the usual time at the glass pane. This means you will be able to feed them by hand (remove cream and soap with a brush under running water) within a few days.
Night light
In nature fish use moonlight or the sun for orientation. If you use a night light programmed with a timer which should overlap with the daytime light, you will help your fish to maintain their sense of orientation and makes them less jumpy.
If the light is switched on suddenly in a dark room it can happen that the discus fish are so startled that they start to "shoot" around the tank, jump out of the aquarium or even ram the glass panes. The impact against the glass panes can even cause death (e.g. fractured skull). Using a night light will avoid these risks.
Where to place your discus aquarium
Put your discus aquarium in a lived-in area of the living room since our discus fish are used to people and enjoy company. Ensure that the aquarium is not exposed to direct sunlight since this will encourage algae. Nor should you place the aquarium behind a door since this will make the fish more jumpy.
Introducing fish after transport
It is very important to introduce the fish properly into the aquarium after transport (described in detail in "Introducing fish after transport". Please note the following:
1. Adjust the temperature slowly (keep the fish bag closed so that the oxygen cannot escape)
2. Ajust the water (open the fish bag and allow some water from the aquarium to flow in)
3. Put the fish in a transport box or bucket and use a net to move them gently.
Throw away the water used for transport and do not add it to the water in the aquarium since it will be contaminated strongly from the transport and would lower the quality of your water.
Difference between adjusting temperature and water
The temperature is adjusted when fish bag is closed by placing the fish bags in a transport box, for example, and adding aquarium water around them. This will adjust the temperature of the water slowly. If the difference in temperature is less than 4 °C the water can be conditioned.
Adjusting the water is done when the fish bags are open. NB: the fish should be put in the aquarium a maximum of 15 minutes after opening the bags otherwise they would suffer from a lack of oxygen!
When adjusting the water, add around the same amount of water from the aquarium as is contained in the fish bag.
After that you can put the fish in a tub, a bucket or a transport box and use a net to place them gently in the aquarium. *See also "Introducing fish after transport")
Changing the water
Leave the cold tap running for c. 5 minutes so you do not use
water for the aquarium which has been standing in the pipes. Warm water is
normally heated in boilers which often contain copper pipes which can contaminate
the water in the aquarium. You can also use a shower head to fill the bucket
(held at a distance of 10-20 cm - this will remove chlorine residue). Then pour
the fresh water carefully from the bucket (which should be used solely for this
purpose) into the aquarium. Repeat the process until the former level of the
water is reached. Clean your hands thoroughly of the remains of soap and any
chemical residue using a brush under running water before you place your hands in
the aquarium!
Tips when on holiday
Most fish die while you are on holiday because your neighbour means well but feeds them too much. We recommend not feeding the fish while you are away. Discus fish larger than 10 cm and other semi-grown fish can survive quite well without food for 2-3 weeks. Larger and older fish can survive even longer, from 1 to 2 months.
These periods of fasting occur naturally and can have a positive effect on health. You will not need to change the water during this period since the lack of food will mean hardly any contamination. Please remember:
- control the aquarium light via a timer
- leave an additional (second) pump/filter running permanently as a backup (do not connect it to the light timer by mistake!)
- lower the water temperature to 27 °C (lessens the appetite of the fish, makes them calmer and lowers their metabolic rate).
When you come back you should only feed the fish a little and increase the amount gradually. The fish and the filters have to adjust back to the normal amount of food (increase number of bacteria/filter performance).
Aquarium insurance
We recommend taking out insurance for your aquarium for the unlikely event that it might leak, e.g. when changing water or if the glued joints start to leak.
Normally you can take out additional insurance for the aquarium as part of your house insurance. This additional insurance is not expensive and is to be recommended since water damage often results in high costs (water may drip through several floors). You can exclude this risk.
Water temperatures and influence on fish behaviour
Normal temperatures for keeping discus fish lie at 29-30 °C.
If your fish are too calm and do not eat greedily but are hesitant about eating, raise the water temperature for c. two weeks to 33 °C. This will raise the metabolic rate of the discus fish and encourage their appetite and their sense of hunger.
If your fish are very active, aggressive and fight each other
you can "cool down" the temperament and aggression of your fish by lowering the
temperature to 27 °C.
Summary of preparations for your discus aquarium
1. Set up the aquarium and clean it
2. Istall aquarium equipment
3. Fill with water (see "Changing water") and connect the power
4. Run in the filters ("feed" the empty tank for two weeks), create bacteria culture
5. Select fish at breeder's and decide on your stock
6. Introduce the fish
7. Feed regularly, measure the water values and change the water when you clean the quarium.
Emergency kit
1. Activated carbon bags (from pet stores)
Activated carbon will filter any toxins from the water. Remove the bag with the activated carbon from the tank after three weeks at the latest since the carbon will release the toxins back into the water when it is saturated. Activated carbon can be stored for years without losing its properties.
2. Quarantine tank
60 litre complete set with heating and filter, thermometer and outlet stone. (For heat therapy or quarantining sick, emaciated fish).
When purchasing new fish, first introduce them to a fish from your current tank in a quarantine tank to see how they get on. Treatment involving temperature should be carried out in the quarantine tank to avoid damaging the plants in the normal aquarium.
3. Antibiotics for emergency treatment
E.g. Neomycin (2 grams per100 litres of water)
Salt baths for treating infestations of parasites
If your discus fish have ectozoons (spots on their skin or the fish start rubbing themselves) we recommend treating the fish with salt water.
The easiest way is to dissolve 500 grams of iodine-free table salt in 15 litres of water from the aquarium (in a clean bucket without residue from cleaning agents). When the water turns clear (after c. 5 minutes) you can place the affected fish in the saline solution. Take the fish out again after 30-60 seconds and put them back in the aquarium. All ectozoons on the mucous membranes of the fish will remain in the salt water and the immune system of the fish will be better able to deal with the parasites remaining in the aquarium.
NB: never leave fish in the salt bath for longer than 50
seconds!