water changing

Right now I have just setup a 225 gallon aquarium and moved my fish from a 100 gallon. What is the minimum water change schedule? and optimal? (being still 50%?) Previously I was changing 50% every week, and the old parameters were - pH 7.8 - Ammonia 0, Nitrite 0 - Nitrate 10 - 30 Aquarium...

So my largest tank is definitely tiny to most on here its abit over 500lts then i have a 350 ltr and a 250ltr For the first copule years i didnt mind marching out 1million trips to the laundry and back with a 20ltr bucket but these days not so much. So i wonder if i can use my garden hose to...

Still very new here (and learning where to post!!) I have a 10g internal filter tank w/ 3 rosy red minnows I bought a lil over a mo. ago. 2 are about an in. perhaps long, and the 3rd closer to 2 in. (all bought on same day/same place). I have been changing 10% of the water once per week w/ my...