Rena XP4/Cannister Filters

[djmatthewblack]

I've been running this cannister for about 2 months now and it has gone to crap. It use to push really strong but now the water barely comes out of the discharge. It is constantly getting air stuck and the bubbles grinding in the can makes alot of noise. The motor itself use to be quiet but isn't anymore. It is practically brand new.

I am running the filter on a 90 gallon planted tank. I've clean the filter several times, replaced filter fabric, but with no luck. It isn't even strong enough to push air bubbles out of the tubing. The water runs into an overflow/bulkhead at the bottom of the tank, and the discharge is out a stand pipe.

But I can pinch off the discharge and it doesn't even effect the filter, it is barely doing anything.

Luckily I haven't had any problems with water quality and the tank is understocked.

This is my first cannister filter so I don't know if it is just a piece of junk or if any other filter would be different.

[geoff_tropheus]

Was the canister new or used when you purchased it?

Sounds like to me your filter is plugged either the inlet strainer or the media.

The Rena Series also has that filler cap on the suction side that if it is loose could also be causing siphon loss and air to get in.

About the only time I have this similar issue is if the fine pad is clogged or the other mechanical foams are soiled to the bone, or..plugged with snails. Got snails in the tank?

[djmatthewblack]

It was a new cannister when I bought it.
I've cleaned the filter but I'm about to do a water change and clean it again. Does the order of the baskets really matter? I have them in there in the order how the box came.

Where's the filler cap located?

I have removed one snail but the shell was too big to go into the intake. It was a mystery snail and I got the trap door out of the intake tube, I could see it.

Just hoping the motor isn't burned out already.

[geoff_tropheus]

The filler cap is a black screw cap on the high point of the suction intake tube. Sometimes if it is not tight, it may leak air and cause siphon problems.

You may even need to use teflon tape on it to seal properly.

The cap is what you use the first time to fill the suction side, that is then used to start your siphon that fills the canister. Then your to wait 2-3 minutes afterwards once full, before you plug in the filter.

I would take apart your suction tubes make sure they are clean.

The order of the baskets probably does not matter much, but I would stack them like the box says for optimized performance.

The bottom basket should be the one that contains the 4 black sponges. The next two baskets should be packed with some kind of bio material such as the ceramic rings or bio-chem stars.

The final top basket should be your fine filter media and or any chemical media you plan to run, such as the Bio-Chem Zorb that came with it or some other fine/chemical media. Then the final top of that basket should be the fine pad. Then put the lid on the last basket, and make sure your pump head seats squarly on top of the filter and clamp it closed.

I would take apart your tubing and just amke sure your not having some plant or snail plugging it up.

Hope this helps...if not I may still have a extra impeller assembly if needed.

Just let me know.

Geoff

[spyke1969]

On my xp 2 I had the intake side inside the filter fill up w/ planted material once, it took a good while to find it!!

[spyke1969]

BTW, My xp2 has been up & running for 2 yrs w/ no probs, except for that 1 time!!

[djmatthewblack]

I got around to taking it apart and sure enough, the intake had plant material stuck in it.

The filter still gets air in it all the time even though that filler cap is on tight. I don't think the carbon is going to do anything with all the oxygen that gets churned constantly in the filter.

Also it is just really noisy when the air is in there churning.

[djmatthewblack]

I got everything unclogged, there was a nerite in the intake and now the thing is pumping like brand new.

Only problem is there is still air coming into the system, rather than churn in the can it is being discharged from the standpipe. If the oxygen is doing this then my carbon setup is going to be worthless right? The air bubbles can't be both oxygenating and carbonating the water can it?

[djmatthewblack]

Okay, and this is interesting, I read some on priming the filter. And when the lever is up, I don't get the air churning, (when the power is on). But when the lever goes down, the air starts to churn. WTF?

I suppose I could leave the lever partially up and that would fix the problem.

[geoff_tropheus]

Sounds like your pump is cavitating and causeing air bubbles. You might want to make sure again your not plugged in the intake. Make sure the top basket is not plugged up, and the pump cover is clear. "the circluar disk" that covers the impeller eye.

[geoff_tropheus]

Did you try Teflon tape on the filler cap?