first time using a canister filter... have rattle that won't go away

[pennyg]

when I got a 120g tank I got an Oase canister filter on the advice of the guy at the aquarium store. I loved it at first but since I have opened it up to place some Purigen in one of the trays, it has a constant rattling and it is driving me bananas. I have tilted the canister slightly several times and do get a few air bubbles out of it which in the past has solved any noise issues. I have only had it about 4 months? I have not run it (after water changes and other cleaning)
without using the hand pump to get as much air as I can out first. So I don't think I have damaged any of the parts by dry running. I am clueless on how to troubleshoot the problem since I have no experience to fall back on. I just want my nice silently running filter back. If you have any advice, please help?

 

[Rocksor]

The problem is that you have too much air in the impeller well as a result of opening the canister. If you reconnect the canister that is filled with water, and has both water in the input and output tube, it will be very difficult to get the air out of the main chamber. The air is basically sandwiched between water. The priming mechanism is used to remove that air. I hate priming mechanisms on canisters and don't use it, since it's another piece for a failure point. So in your case, disconnect the canister and move it off to the side. You will have water in both the input and output tube. Open the output tube over a bucket and drain the water out of it. If the output bar is under water, you will have to make sure it is no longer submerged. Reconnect the canister if no more water is coming from the output tube. Wait a few minutes and see if enough of the air came out after reconnecting.

In the future, when reconnecting canisters to the tubing, I make sure there is no water in the canister and no water in the output tube. I also make sure the input tube has water. This will allow air to escape as the canister fills with water from the tank through the input tube. If there is a spray bar on the output, I disconnect that or make sure that there is no water in the spray bar.

 

[pennyg]

So what I am picturing in my head is that I disconnect the inlet/outlet part of the canister. Then I disconnect the outlet hose from there and allow it to drain into a bucket...reconnect outlet hose. Then reconnect inlet/outlet part onto canister. When I engage the lock on the inlet/outlet, the main chamber of the canister will be filled by water coming from the tank in through the inlet hose and air from main chamber will be pushed out the outlet hose? Will I still use the primer pump before starting the filter back up? I will definitely try this asap after work today. THANKS!

The problem is that you have too much air in the impeller well as a result of opening the canister. If you reconnect the canister that is filled with water, and has both water in the input and output tube, it will be very difficult to get the air out of the main chamber. The air is basically sandwiched between water. The priming mechanism is used to remove that air. I hate priming mechanisms on canisters and don't use it, since it's another piece for a failure point. So in your case, disconnect the canister and move it off to the side. You will have water in both the input and output tube. Open the output tube over a bucket and drain the water out of it. If the output bar is under water, you will have to make sure it is no longer submerged. Reconnect the canister if no more water is coming from the output tube. Wait a few minutes and see if enough of the air came out after reconnecting.

In the future, when reconnecting canisters to the tubing, I make sure there is no water in the canister and no water in the output tube. I also make sure the input tube has water. This will allow air to escape as the canister fills with water from the tank through the input tube. If there is a spray bar on the output, I disconnect that or make sure that there is no water in the spray bar.

 

[Rocksor]

You shouldn't need to use the primer, i never do.

 

[pennyg]

This did not fix the problem. It might be louder now than before.
I will try opening the canister and removing some water although I have to syphon it because the pre-filter is too tall to be removed without tilting the canister and spilling water under the tank stand. I underestimated the amount of vertical room under my stand and set myself up for not having enough space to lift the pre-filter out. But until I fix the noise problem I am not going to try to get new hose and cut it so I can have the canister sit outside of the stand beside aquarium.

You shouldn't need to use the primer, i never do.

 

[pennyg]

ah, update... I removed the pre-filter which is also the manual primer. I disassembled it, rinsed it out and reassembled carefully. Put everything back together, making sure the outlet hose was empty. I waited until I thought the chamber was filled with water, then powered up. The rattle is gone. I think it was something in the pre-filter not put together correctly the last time I had it apart to clean it. However there is still a trickling sound coming from inside the canister or possibly the primer? The trickle is not loud but it is definitely not as silent running as it was when I first set it up. So either there's still a pocket of air or the sound is because I removed a sponge filter and put a mesh bag of Purigan in that level so it will just make more swishing and water sound now? The trickle sound is not loud at all, barely noticeable with the cabinet closed and quieter than the big HOB I have running on my 55g African cichlid tank. I am okay with it as long as it doesn't damage the canister impeller.
Thanks for the help! MFK folks are the best!

 

[Rocksor]

The sponge filter versus the purigen shouldn't make a difference. You may still have a little air. Check in about a 3-4 days, typical time for more air to get purged out. Next time make sure the canister does not have any water when you reconnect it.