I have a canister filter rated around 500 gph on a 55 gallon tank. The fish is 3 9" oscars. I was told if I "over filter" my tank then I wont need to ever do water changes as long as I occasionally rinse the filter media. True? This seems like legit advice but I'm skeptical
Do i need to do water changes if i have good filter
- Thread starter Ender024
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I'm hoping this is a joke but I believe you're being serious.
Even if you have a million gallons per hour you'll still need to change your water.
As for your tank.... 3 nine inch oscars in a 55.... I hate to break it to you but that tank is much too small for those fish. Maybe a 180? I'd immediately start doing 50% water changes daily for a week to hopefully get your water parameters back under control.
Pic of the tank with the oscars?
Even if you have a million gallons per hour you'll still need to change your water.
As for your tank.... 3 nine inch oscars in a 55.... I hate to break it to you but that tank is much too small for those fish. Maybe a 180? I'd immediately start doing 50% water changes daily for a week to hopefully get your water parameters back under control.
Pic of the tank with the oscars?
Filters won't stop the need for water changes. As said a 55 is too small for even 1 Oscar. I've seen them over 16 inches a 55 is only 12 inches deep.
Many would say no. I would think it would ok if they stay under 13 inches(clean water would be a must).
It's a shame many people get oscars when they're cute little 2 inchers not knowing how big they'll get or what's really needed to take care of them.
Hmm. The answer to the question is yes you do need to do water changes.
Oscars are extremely messy fish. They chew up their food and spit most of it out. They pee lots. Have you ever seen an Oscar poop? Especially when you feed them crickets...it almost doesn’t even make sense that something so big can come out of that little hole. The filter doesn’t remove most of these things, they can be broken down to a certain extent but you will still be cycling the same water over and over again.
There could almost be an entire thread or even a sticky about how big of a tank oscars require. The truth is your fish may be alive in that 55 gal tank but they most likely are not thriving. Imagine you had 2 roommates who were absolute slobs and didn’t clean up after themselves, and you all shared a room. And that’s all you had to live in. And you have to crap and pee in the same room. But someone has an air purifier in the room so they don’t think it’s a big deal so they just keep giving you more food....
Just sayin.
Oscars are extremely messy fish. They chew up their food and spit most of it out. They pee lots. Have you ever seen an Oscar poop? Especially when you feed them crickets...it almost doesn’t even make sense that something so big can come out of that little hole. The filter doesn’t remove most of these things, they can be broken down to a certain extent but you will still be cycling the same water over and over again.
There could almost be an entire thread or even a sticky about how big of a tank oscars require. The truth is your fish may be alive in that 55 gal tank but they most likely are not thriving. Imagine you had 2 roommates who were absolute slobs and didn’t clean up after themselves, and you all shared a room. And that’s all you had to live in. And you have to crap and pee in the same room. But someone has an air purifier in the room so they don’t think it’s a big deal so they just keep giving you more food....
Just sayin.
Here’s a better understanding on WHY we do water changes:
Your filter picks up waste. (Uneaten food, poop, etc)
The live bacteria break down the waste and it becomes ammonia as it decays.
This broken down waste becomes nitrite.
This nitrite gets absorbed by a different kind of bacteria, then output as nitrate.
Ammonia, being the most toxic, nitrite still toxic, and nitrate is much more tolerable in small concentrations.
In a tank with a filter alone, the nitrate ends up adding up and eventually becoming toxic to your fish.
The water change dilutes the amount of nitrates with fresh water. Thus, making the nitrates less toxic since it’s now a lower concentration.
IF you wanted to do LESS water changes, you could add live plants to complete the nitrogen cycle and absorb all the nitrates.
Now on the topic of filtration:
Over filtration is better. Yes.
Oscars, very messy fish. They will REQUIRE over filtration. So your “over filtration” becomes standard filtration for your stock.
Your filter (canister) is only so efficient. That being said, even with the canister on a small tank, some waste stays inside the tank. (Stuck in the gravel, sand, decorations etc.) your water changes will help remove this waste that is decaying inside the tank, never having made it to the filter.
And canister filters are known as “nitrate factories” because while they hold tons of media, the increased bacteria can handle much more “cleaning”, and all this broken down organic material remains inside the barrel of the filter. Until it is removed from the tank AND filter, your tank still won’t be “clean”.
So bottom line here is this:
Your canister is decent for your tank and stock. It will need to be cleaned frequently.
You will also need to perform routine water changes.
It’s a necessary evil in the hobby.
For a “low maintenance system”, do some research on the “Walstad Method”.
Your filter picks up waste. (Uneaten food, poop, etc)
The live bacteria break down the waste and it becomes ammonia as it decays.
This broken down waste becomes nitrite.
This nitrite gets absorbed by a different kind of bacteria, then output as nitrate.
Ammonia, being the most toxic, nitrite still toxic, and nitrate is much more tolerable in small concentrations.
In a tank with a filter alone, the nitrate ends up adding up and eventually becoming toxic to your fish.
The water change dilutes the amount of nitrates with fresh water. Thus, making the nitrates less toxic since it’s now a lower concentration.
IF you wanted to do LESS water changes, you could add live plants to complete the nitrogen cycle and absorb all the nitrates.
Now on the topic of filtration:
Over filtration is better. Yes.
Oscars, very messy fish. They will REQUIRE over filtration. So your “over filtration” becomes standard filtration for your stock.
Your filter (canister) is only so efficient. That being said, even with the canister on a small tank, some waste stays inside the tank. (Stuck in the gravel, sand, decorations etc.) your water changes will help remove this waste that is decaying inside the tank, never having made it to the filter.
And canister filters are known as “nitrate factories” because while they hold tons of media, the increased bacteria can handle much more “cleaning”, and all this broken down organic material remains inside the barrel of the filter. Until it is removed from the tank AND filter, your tank still won’t be “clean”.
So bottom line here is this:
Your canister is decent for your tank and stock. It will need to be cleaned frequently.
You will also need to perform routine water changes.
It’s a necessary evil in the hobby.
For a “low maintenance system”, do some research on the “Walstad Method”.
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Your filter handles the nitrogen cycle and physical particles like uneaten food and poop.
Basically, the fish eat/pee/poop and as the waste breaks down it becomes ammonia. Bacteria then show up to "eat" the ammonia, they then produce a chemical called nitrite. Both ammonia and nitrite are deadly to fish so a different kind of bacteria appear to "eat" the nitrite and produce nitrate, nitrate isn't deadly but is harmful in large quantities.
This takes place anywhere with water flow and oxygen. Most of the bacteria will live in your filter as that's where they're likely to get the most "food".
None of the bacteria "eat" the nitrate. Nitrate is removed by doing weekly water changes.
So, in short, no. No amount of canisters is going to eliminate the need for water changes, they have to be done.
When you do your water change keep a bucket of old tank water aside and give your filter media a nice swish in it. This will remove all the gunk on it so the bacteria can flourish and help keep tour system healthy.
Also, three oscars in a 55?! Jebus...
Basically, the fish eat/pee/poop and as the waste breaks down it becomes ammonia. Bacteria then show up to "eat" the ammonia, they then produce a chemical called nitrite. Both ammonia and nitrite are deadly to fish so a different kind of bacteria appear to "eat" the nitrite and produce nitrate, nitrate isn't deadly but is harmful in large quantities.
This takes place anywhere with water flow and oxygen. Most of the bacteria will live in your filter as that's where they're likely to get the most "food".
None of the bacteria "eat" the nitrate. Nitrate is removed by doing weekly water changes.
So, in short, no. No amount of canisters is going to eliminate the need for water changes, they have to be done.
When you do your water change keep a bucket of old tank water aside and give your filter media a nice swish in it. This will remove all the gunk on it so the bacteria can flourish and help keep tour system healthy.
Also, three oscars in a 55?! Jebus...
You beat me to it. And with a better explanation lol