Tank Accessory

i have an iternal filter for my 5" tank but why is the water turns green after a few days?

what are the essiential accessories that i need for a tank?

Some essentials are - more than 5" of water. What are you planning on keeping in your little tank?

the green water is from algae. Filtering won't help. Algae is a plant growth that occurs from too much light and too many nutrients (nitrates and phosphates). If you cut out the light, the algae will die off.

But seriously, what are you going to keep in a tiny tank?

Here are the essentials for setting up an aquarium:

Get the absolute largest tank you can afford - 75 gallons+ is not too large.
You need a filter or two, plus media for it -
themometer
heater
gravel
tank top with light source
test kits for ammonia, pH, nitrites and nitrates
water dechlorinator
fish food
fish
plants - if you want
tank decorations - if you want
Bucket
siphon to aid with cleaning

The kind and number of fish that you wish to keep will determine the best size tank.

Your tank water needs to mature or cycle - This means allowing the ammonia level to spike, followed by a spike in nitrites and finally, a 0 ammonia and 0 nitrite level and and nitrate level less than 40 ppm. Then you are ready to add a few fish. This could take 4-6 weeks.

When you start adding fish, add just a couple every week, so your biological filter can keep up with the additional nitrogenous wastes from the new fish.

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