Please use caution when changing water. You need to make sure you've used a dechlorinator/conditioner to remove chlorine from city water supplies. Some city water uses chloramine which will release ammonia as the chlorine evaporates are is removed with a binding agent in the conditioner.
Chlorine will kill fish quickly.
You will want to try your best to match temperature too. I usually leave two 5 gallon jugs out to get to room temp. I keep the tank at 76, so I'll add about 2.5 gallons at a time and let the heater do its thing. This is more of a winter problem though. I'm averaging 20% water changes a week.
I use a gravel siphon and dump water into a 5 gallon jug so I know I'm removing precisely 10 gallons and adding 10 gallons, with some fudge factor for evaporation.
There is no reason you couldn't change higher percentage of water, in fact if you're not properly cycled (nitrogen cycle) you may have to. The old school of thought was that you're harming the colonies of beneficial nitrifying bacteria but we know now that there is very little of this bacteria in the water column and largely in the filter with smaller percentages on the surfaces in the aquarium. The most problematic part of large water changes is maintaining stable parameters, temp and ph, gh being the most likely parameters to shift too quickly.
I keep my ph buffered with crushed coral in mesh bags in my canister filter. It's almost always right at 7.8 no matter what I do. Coral is quite fascinating.

It's more fun to be a victim

There will never be an effective vaccine. I'll never get one anyway.

You can do more if you want.. guys with large fish will do as much as 80% at a time. There is math involved that shows why you want to do this but these guys will also do 3 a week. When I had my ome tank set up it was 350 gallo s of water upstairs hooked up to a 120 gallon sump in basement. I actually consistently added water to the sump and every day would shut pumps off for a seconds that would than siphon the sump down to about 25 gallons of water. I’m trying to remember if it filled fast enough to auto siphon or not. This system worked great for when I was setting tank up,and it was mainly smaller fish as nitrates stayed extremely low.

On the other hand, when i switched to the planted discus tank it was a harder as the plants were a higher light requiring variety to deal high tank temps and had to be dosed with minerals. It was a pain in my ass even if at peak tank it was beautiful. After a couple years of that and a 3 year old killing all my fish I switched it up to a South American cichlids tank that just needed more water flow than this system provided so I changed to a canister system.. still not enough and I’m going to tear it down and go back to original in a community setting vs a specialized.

Many that is true, but an incomplete statement.

Many that is true, but an incomplete statement.

my dad has a 180 gallon one, freshwater. mostly smallish cichlids, used to have a few oscars. as long as you clean it once a week and change at least 15%ish of the water each cleaning your fish should be fine. messed around with live plants for a bit and those were annoying

Many that is true, but an incomplete statement.

Many that is true, but an incomplete statement.

Updated tank shot.
Https://imgur.com/a/3tg2jSX

For whatever reason I can't embed the image. It just shows up as "can't define image size"
Works if you click it.

The wife added some angelfish.

I just cleaned the filter Sunday. Took about an hour and I broke the impeller shaft. Fortunately, I had thought ahead and had a motor maintenance kit on hand. Saved the lives of all our friends.

The Java moss is going bonkers. I cut off a baseball sized amount every week now. I added some stem plants. Egeria densa. It mostly died off adjusting to the water parameters but now the new stems are growing nicely. Finally. It was a battle. So if anyone wants a shitload of free Java moss, it's yours.

Although it's technically overstocked the plants are just downing nitrogenike crazy. 0ppm ammonia, 0ppm nitrite and less than 20 ppm nitrate, almost undetectable nitrate as of my chemistry tests tonight.

Because you are stupid, maybe read some books educate yourself.

We walk, talk, and won't shit our pants

Do you have a ship wreck, diver, or buried treasure?

Many that is true, but an incomplete statement.

Nice job. Impressive.

Many that is true, but an incomplete statement.

Now that I'm a semi retired empty nester with just the occasional dog and an outdoor alley cat of four years, this sounds intriguing.

Many that is true, but an incomplete statement.

I'll help.

We sometime just sit in a dark room and listen to music and watch the little dudes swim around.

Tomorrow they get a cucumber slice. Big day!

I don't like white rappers.

Thanks brother, I'll let you know.

Many that is true, but an incomplete statement.

Fish eat cucumber?

Many that is true, but an incomplete statement.

Didn't you rail on the Shedd Aquarium for keeping fish captive?

Many that is true, but an incomplete statement.

I don't like white rappers.

Many that is true, but an incomplete statement.

Thanks!

We sometime just sit in a dark room and listen to music and watch the little dudes swim around.

Tomorrow they get a cucumber slice. Big day!

Wow. You found puffers easy? That's a tough guy to keep happy.

I don't like white rappers.

I liked red bellies. I was and am half tempted to go that way again but they do get boring. They also are striking fish as they get older. I tried a brackish tank once when I lived in Montana but it was near impossible to get fish in. Puffer’s are cool but it’s hard to keep their teeth worn down. I thought the South American ones were cool as hell but their beaks grow like crazy.

Many that is true, but an incomplete statement.

I am just really appreciative of the fact that people get as stoned as I do apparently.

Sans aquarium.

I don't like white rappers.