Took canister offline!

[Frank and beans]

Hi!
Because of an ongoing nitrate issue (100+), I took my canister off finally in 2 parts as not to shock the tank 2 weeks ago and to my horror my nitrates are the same!! How can this be? With all the clogged rotten smelling pads gone and there's no change? This tank is a 55 gal SW and it's been up for 4+ years. I was a newbie then and I believe I made some bad choices and given bad advice to set it up so yes it has had high nitrates ever since the go. I know I'd do it differently if I did it again but now to help this tank what else can I do? I've got a 125 gal aqua clear filter on there for the last 6 months, over filtered, reef octopus skimmer, and the canister is empty now just using for flow. I'm so frustrated any advice would help!
Thanks everybody :/

 

[BrettDS]

When was the last water change? Definitely start doing regular water changes if you aren't already.

 

[Frank and beans]

Ok I will start with that! I actually did not do a WC since I took canister off and should have. Thanks for advice.

 

[BrettDS]

Took canister offline!

Nitrates are the byproduct of the nitrification cycle in your tank. Living things produce ammonia, which is turned into nitrites, then nitrates. The traditional way to remove nitrates has been to do water changes.

There are some alternate ways to remove nitrates from your tank, such as using a deep sand bed that will allow anaerobic bacteria to consume the nitrates or more recently, using Chaeto algae to consume the nitrates, then physically removing some of the Chaeto (and the nitrates it contains) periodically, but if you don't have a DSB or Chaeto then your only option for removing nitrates is doing water changes.

 

[BrettDS]

Took canister offline!

People call canister filters nitrate factories, because they can trap a lot of waste and the only thing they do with it is break it down and turn it into nitrates, but keep in mind that the waste will still exist in your tank whether it's trapped in your canister filter or not. If you have a good cleanup crew they may consume some of the waste and help prevent it from turning into nitrates, but they will never be close to 100% effective and without a CuC at all the waste will still nitrify whether it's in the canister filter or not.

 

[BrettDS]

Removing the canister filter may slow down the rate that your tank produces nitrates, provided you have something to help consume the waste, but your tank will still produce nitrates no matter what and without a DSB or Chaeto to remove the nitrates then water changes are your only option.

(Sorry about the multiple posts, I'm typing this on a mobile device and I kept hitting send instead of return to start a new paragraph)