Alessa

you can do that if it is to let cold water adjust to the room temperature by itself which is not necessary. what I do is just take out the water as you said, pour it in the sink/toilet/etc... then, add fresh water to the bucket (making sure it is about the same temperature as the one you took out) add dechlorinator (aka conditioner) and add it in the tank.

jdhef

Except that while cycling with fish you should be taking out 4 or 5 gallons. Afterwards, your Nitrates will be your guide. Nitrates shouldn't rise above 20ppm, so if you are only changing 2 gallons per water change, you could end up doing water changes every couple of days.

Steve113

I just use boiling water from my spare kettle to raise the temp in my replacement water to the same as my tank.

Top tip:
When you put the water back in, I find it easiest to syphon it back in to the tank using the vac as this does not disrupt your gravel and plants - and strong currents don't stress your fish. If you pour it in to the tank straight from the bucket it messes your tank up.

Devon

Welcome to FishLore, and the fish keeping hobby!!

You've come to the right place if you're new and have questions. Don't hesitate to start a thread if you need help with anything, people here are usually very fast to answer and always friendly.

Since you're cycling with fish you want to do 50-70% water changes daily until you're cycle is complete, depending on your stock. After that a weekly water change of 40-50% should suffice (provided you're not overstocked!!)

Sounds like you already need another tank... here comes the MTS, I think.