How Much And How Often Water Change In A 2.5 Gal Tank?

Discussion in 'Water Changes' started by Arrielle, Apr 17, 2019.

  1. ArrielleValued MemberMember

    How often and how much should I change the water in a:
    - 2.5 gal tank
    - 1 fish - betta
    - heater
    - sponge water filter attached to an air pump

    Thank you.

    PS. This is a temporary home. Not sure when I will be able to move him in a bigger thank - but I am aware of the need.
  2. RyanC14Valued MemberMember

    Weekly 10-20% should be good

  3. mattgirlFishlore VIPMember

    I would change out at the very least 50% of the water every few days if this tank isn't cycled. Be sure to temp match the new water to the tank water and use a water conditioner if you have chlorine/chloramines in your source water. Fresh clean water will keep your little guy healthy.

  4. TheBettaSushiWell Known MemberMember

    If it’s cycled, a 20%-30% once a week should suffice. If it isn’t cycled, I’d do 50% every other day at least and test your parameters using the api master kit as it will help determine how much water to change. Mine is in a cycled 6 gallon and I change about 30% once a week.

  5. bitseriouslyWell Known MemberMember

    With a tank that small, decent changes are easy. I also have a betta in a 2.5, and I use a juice/drink pitcher to change water. Actually, 2 of them (yay dollar store).
    I use a small plastic cup to remove water from tank and fill one pitcher. Then I fill the second pitcher with new treated and temp matched water, using the first pitcher as my reference temp guide. Then pour the new water in slowly over a spoon. Put a bend in the spoon to make it super easy. :)
  6. ArrielleValued MemberMember

    Good pieces of advice. Do you use your tools intangibly or each tank has it own tools? I actually have 2 bettas in identical containers / conditions.
  7. bitseriouslyWell Known MemberMember

    Gotta be honest, no I do not. But my tanks are all long(ish)-running, and stable with no new or recent additions.
    But, I have a quarantine tank that DOES have its own tools, to avoid cross-con in that situation.
    I also believe that proper rinsing under running tap water immediately after use is 95% as effective as different tools or sterilization treatments. Yes, I know it’s not 100%.
    Another helpful practice is task-separation. If I have to do water changes on a quarantine/hospital tank and a healthy tank, I’ll do the healthy tanks first, finish that job, then do the q-tank. That way there is no possibility of water/particles from a possibly diseased tank getting to the healthy ones. The reverse is not true, but it would carry little to no risk.
  8. ArrielleValued MemberMember

    I wanted to type "INTERCHANGEABLY" This auto-correct

    OK. Here are my tanks / fish. I use a tube to take the water out and I use the same tube. I have a one YO betta plakat Koi and a new betta plakat white. Because the white one seems healthy, I used the same tools for both. If will not forgive myself if I kill the old Koi one. He is a very beautiful one - and it was expensive. I don't have a clear picture of him now.

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  9. TheBettaSushiWell Known MemberMember

    Yeah I don’t. I use the same and rinse and soak them in tap water (which my tap has a good amount of ammonia). I then let it air dry before using it again. If I had a qt tank, I’d take care of the healthy tank first then move on to the qt as to not possibly contaminate the healthy tank if something was lurking in qt.

    I should definitely invest in another siphon at least to use for qt only. However, my stocking is full with a betta and nerite in my 6 gal.
  10. Dch48Well Known MemberMember

    Once the tank is cycled, I would do a nitrate test once a week. If the nitrate level is less than 20, don't do anything. If it's close to or above 20, change out at least 20% of the water. The less changes and fluctuations of water quality the better. In a small tank, a water change can cause larger fluctuations. 2.5 gallons is okay for a Betta but I wouldn't go any smaller.
  11. ArrielleValued MemberMember

    Thank you. I do not have yet any water testers. The API seems to be recommended by most. Does API has a test for nitrate? ( if you are familiar with the test kit). Thank you
  12. TheBettaSushiWell Known MemberMember

    The master kit tests for ammonia, nitrite, nitrates and ph (high range included). It’s $23 on amazon which is much cheaper than purchasing it at your local pet store.
  13. Dch48Well Known MemberMember

    Stocking is not really that full. I have kept my Betta for a year now in a 3.5 with a Nerite and for the first 9 months a Mystery snail that got pretty big. Now there are a Tiger Nerite, a Zebra Nerite, and a very small unknown type Nerite in with the Betta. They are there to mainly keep brown algae under control and just one was not keeping up with it.

    My other 3.5 gal. tank has 2 male guppies, 3 Neocaridinia shrimp, 2 Dwarf Cajun crayfish and a Tiger Nerite plus 7 different types of plant life and it's doing great.