TFA101

I haven't cleaned my tanks for about a week and a half now. What's the longest a tank can be left without cleaning? I have a ten and twenty gallon if this info is necesaary.

Peterpiper

To me, weekly water testing is important, and is the first step.
The results of you testing will govern what needs to be done in regards to water changes. Readings of Ammonia or Nitrites will require you to do larger water changes and address the issue of why you have the readings.
Nitrates. As every system is different, Nitrate build up will vary from one system to the next. Some things that affect Nitrates include, Filtration systems, Skimmers, Algae's, Plant's, Feeding, Volume and Stocking levels. A large tank, lightly stocked, running a good skimmer with plants and Algae's will have a lower Nitrate build up than a tank that is heavily stocked, has no plants or Algae's and is not running a skimmer.
If you find that your Nitrate levels are slowly going up when you do your weekly tests, then you will need to increase the % of your water change. Good reason to have low stocking levels, large volume, good filtration and some nice Algaes.

susitna-flower

Peterpipers got you covered, he must be a salty dog....

Peterpiper

Bugger, this is fresh water.. must be the salt in my veins.. ok skip the skimmer, and I have never seen good algae in fresh water.. so skip that too. but the rest is the same..

TFA101

ok, thanks. but i have one more question...

i often watch my friends clean their tanks and observe that they put their fish into individual cups or baggies with some of the old aquarium water as they clean out the tank. Im getting scolded because i leave my fish in the tank. I dont have any bettas, but i know they require that. I just want to know if I'm excessively stressing out my fish by leaving them in the tank.

Peterpiper

Leave the fish in. I think it would stress the fish more if you put them in bags once a week. Just when you do your cleaning, go slow and no sudden moves, they will soon get use to your hand in the tank.
Just dont syphon up any fish as they wont like it or you

Tavel

Don't remove the fish, that's a very bad practice. The fish are scared witless (haha, I made a funny) of the siphon and will keep far far away. You may have to keep an eye out for bottom feeders, but they too are usually pretty afraid of it.

Beside having no reason to remove the fish, it hurts them because it's extra handling plus, the extra stress of being in a little cup with no aeration or filtration for an hour.

I should qualify that not ALL fish are afraid of the siphon. I have a suicidal danio that loves to swim into and out of it as it's running. Crazy thrill seeking kids these days. lol

I clean my large tank every 2 weeks and my small tanks every week. The large tank is understocked and doesn't need to be cleaned as often, but it's also a lot of work! It always takes a half hour to clean the large on, but I can do the little ones in 5 minutes each!