[SamJustice]

How often do you make changes in a filter 2.5?
Still twice weekly, one 50% and one 100% ?

 

[Bethydan]

That's about what I do. I test my water for ammonia, and I do larger water changes more often depending on what the tests say. But on average, it's the same.

 

[SamJustice]

cool. Thanks. ^.^ just wanted to make sure before I unnecessarily stress out my little buddy or miss water changes.

 

[Bombalurina]

I believe that with a filter, two 50% is enough, as long as you vacuum the gravel.

 

[Keroro]

How about a full water change every week with a 2.5? Is there a con to that?

 

[Bombalurina]

It allows the ammonia to build up all week, instead of only half a week. Full changes are also more stressful than partials.

 

[Liquid]

How about a full water change every week with a 2.5? Is there a con to that?

You are never supposed to do a 100% water change. It gets rid of all your beneficial bacteria and basically ruins your cycle. Plus it stresses the fish too much.

 

[Bombalurina]

Not true, Liquid. In a 2.5 there is no cycle anyway - less than 5 gallons doesn't really hold a cycle. In over 5 gallons, which has cycled, even a 100% water change won't remove the cycle. Very little of the beneficial bacteria is contained in the water.
What will kill a cycle is replacing or over-scrubbing your filter, which is where 90% of the good bacteria is.