pH was originally acronym for French clause “pouvoir hydrogène,” which can be translated into the English as “power of hydrogen,” “hydrogen power,” or “potential of hydrogen.” pH is used to quantify acidic or alkaline nature of a chemical which is measured in terms of H+ ions concentration. Hence the name pH.

Saltwater fish prefer an alkaline pH of 8.0 or above. Freshwater Fish thrive in a lower range between 5.5 to 7.5, depending on specific species. Arowana is best suitable at 6.0 7.0, which best yet stable at 6.5. Arowana prefers soft water and its colour is best when pH is kept slightly lower such as adding black water extract or peat. Sudden change of pH level could be fatal to arowana as well as other kinds of fish.

Tank size is a very important aspect as it affects how the fish is going to turn out when matured, whether it is straight swimming with fins fully opened or one that is sickly, stunted and hunched. The larger the tank size is, the better. In general, a bare minimum size for an adult arowana should be 5 ft by 2 ft.

One general rule is that the length of the tank must be at least 3 times longer than the length of the fish. As for the tank’s width, it must be at least 1.2 times longer than the length of the fish. It is ideal to place the fish tank in a quiet spot of the house to avoid asserting unnecessarily stress to the fish by human traffic. Surrounding stress can easily affect the fish’s base color, especially for Cross Back Golden.

Sufficient lighting is also required for arowana to ensure good color developments and it is ideal for tanks to expose to some natural morning or evening sunlight. However, too much sunlight can lead to algae problems such as green water or drastic temperature change in smaller tank etc.

Avoid switching on the aquarium light suddenly in a darkened room, or the fish may panic and injure themselves. Switch on the room lights first, then a few minutes later switch on the tank light.

Temperature is best at 26 – 30 degrees unless when treating sick fish. A lower temperature might easily invite diseases while a higher temperature can help to keep diseases away. However, too high a temperature can also cause some of the softer tissues around the head to wrinkle faster.

Temperatures must be maintained as stable as possible be it day or night as great fluctuations can be harmful or kill the fish.

Aquarium heater may be needed as a protection from sudden fall in temperature at night or in unusual weather. It also helps fish to increase metabolic rate, which, in turn promotes frequent feeding that leads to rapid growth.

Nitrate and ammonia are from the waste and urine of the arowana. Nitrate is the by-product of nitrite after being acted on by bacteria in the tanks called “Nitrobacters”.

These substances are toxic and are harmful to the fish in all ways, for example common diseases like gill-turning, loss of appetite, cloudy eye, fin rot etc. It is best to keep them as low as possible. It is recommended to use effective biological or mechanical filter to balance the `nitrogen cycle’.

However, do not leave this job solely to the filter since the best way to to keep these toxic substances always at safe level is to constantly change the water.

Proper aeration is also required to provide sufficient dissolved oxygen content in the water for arowana and at same time maintaining the established nitrifying bacteria in the filters.

Water change can be conducted once or twice per week at 30 to 50 % each time depending on the size of fish, the number of fish in the same tank and the volume of water or capacity of tank.

A general rule is, the bigger the fish, the larger the number of fish and the smaller the capacity of tank is, will require more frequent water changes. Arowanas are extremely sensitive to foreign substances like chlorine.

It is a good practice to add anti-chorine and metal-substances removers to treat new tap water. If space permits, use aged water (ages for >24 hours).

As the pH level of tape water in Singapore and most countries are above 7.0, it is advisable (not a must) to use black water extract to soften the water during change.

This black water extract help creating a natural water environment similar to the wild and is ideal for Asian Arowana.

Alternative, hobbyists can prepare their own black water extract using Ketapang Leaves. These brownish dyes from the leaves have very identical effects as compared to those commercial `black water extract’ products and are commonly used in the industry. However these leaves can only be collected in some tropical countries.

Use only brown crispy dry Ketapang Leaves and rinse them under tap water. For 4ft tank, soak about 4 to 8 leaves together in a pail of water.

Minor aeration and some salts can help to release these brownish color dyes and preserve the leaves. When brownish tea color appears in the water after 2-3 days, they are ready to be used.

Throw away the leaves and apply ketapang leaves extract directly into the tank during water change and stop adding when the tank water displays light brownish tea color. Such dye leaves are commonly used in most commercial fish farms to condition water for soft water fishes.

pH Shock – No doubts Asian Arowana is a hardy fish, proper way of acclimating is still required because water parameter can be very different in many countries.

During transportation, a fish’s natural biological function lower the bag water’s pH. The longer the shipping time, the more the pH will be reduced.

This increases the need for caution and greater care in acclimating new arrivals. Gradually you must balance the pH in the shipping package to match that of their new tank.

• Aged tap water in tank for at least 48 hours ahead before arrival
• Add 0.1% salts and increase aeration in tank
• Add black water extract to soften water if available
• Your aquarium water quality must be Ammonia 0, Nitrites >10 and pH 6.0 – 7.5

It will take 45 – 60 minutes no longer to complete acclimation procedure.

1. Switch off aquarium tank light
2. Float sealed bag in aquarium for at least 15 – 20 minutes to equalize temperature
3. Pull up to open bag or may use knife to cut the tighted rubber bands
4. Add 1 cup tank water and repeat method every 5 minutes until bag is full
5. Empty 1/2 of the water from the bag
6. Repeat water filling step again every 5 minutes until bag is full
7. Submerge bag and gently release the specimen
8. Monitor the fish closely for any abnormal behavior for the first few hours
9. No feeding for first day

Note: Do not open your packages in bright light. Acclimation will be done in dim light. Keep aquarium off for a few hours after to help new fish reduce stress.

Do not aerate the bagged water if the fish are obviously healthy. This will raise the pH too high and put the fish potentially into toxic shock. At home, always keep sponges or cloths under water at all times.