How many wc per week/2weeks?

[duanes]

With such a small tank and one 30% water change every 2 weeks, your pH could have dropped significantly enough making the water change water so drastically different that you created pH shock.
I found to maintain stable pH, and keep alkalinity at an optimum to keep and maintain buffering capacity, a 30% water change every other day is needed, especially in small tanks.
This is especially needed if your tap water has a low alkalinity, mine comes out of the tap at 100mg/L.
High alkalinity keeps pH stable, if yours is low, you may need to do even more water changes, and may need to add a buffer, such as baking soda to your water change water. You water supplier can provide you with that info.

 

[Geraldaw]

Refilling from water tap will kill it? By what mean to stop the chlorine in the water?

 

[Geraldaw]

how do i even test out the ammonia in the tank? using a ph meter or what?

 

[Geraldaw]

i just know that my whole fish became white when dying.

 

[Geraldaw]

If weekly water change. that mean i need to put out 2 pail of water for 24 hours?

 

[predatorkeeper87]

dude. LISTEN to the advice given. Your tank is TOO small. You CANNOT keep an arowana in that small of a tank.

 

[duanes]

A pH meter is to test pH, there are tests available to tell most basic water parameters.
There are box kits, and strips.
Some strips are available at home improvement stores or pool suppliers, many are available at local fish stores. You could start with inexpensive test strips, or if you paid attention in chemistry class, a multipurpose test kit.
They range from about $15 on up into the thousands, depending on how serious a fish keeper you wish to be.
generic multi test strips

Above portable chlorine analyses, below titration cuvettes to be put into a $10,000 photo-spectrometer for ammonia

 

[Kittiee Katt]

Refilling from water tap will kill it? By what mean to stop the chlorine in the water?

Hello, I assume your English isn't the best. Please, listen to what you're being told, use a translator if it doesn't make sense.

If weekly water change. that mean i need to put out 2 pail of water for 24 hours?

Go to the shop that sold you the aro and ask them for a dechlorinator and an AMMONIA TEST KIT, a dechlorinator is a product that removes chloramine and other heavy metals from your tap water. Just leaving the pail out will not remove chloramine or most heavy metals.

how do i even test out the ammonia in the tank? using a ph meter or what?

You can test your ammonia by purchasing an AMMONIA TEST KIT the pH kit will NOT tell you an ammonia reading.

And you NEED a bigger tank, please listen to what the people on here are telling you. You need a tank at least twice the size of what you have to house just one arowana adequately, please listen to these guys!

 

[Geraldaw]

How do i treat the tap water with dechlorine?

 

[Kittiee Katt]

How do i treat the tap water with dechlorine?

Most dechlorinators come in a liquid form with specific dosage instructions on the back. Add the recommended amount to your pail before tipping it into the aquarium - its that simple.

Almost everything available in this hobby, be it test kits, dechlorinator, filters or whatever come with instructions for proper use. Just follow whatever the instructions tell you to do.