RENA Canister filter?
I have a rena xp4 for my 75 gallon aquarium and I was just wondeing is the canister supposed to fill up all the way cause mine fills to about a centimeter below the top so theres still a little air inside but not a lot and it runs fine.
The Renas do this sometimes. While it doesn’t seem to affect them it can lead to problems later on, like noise, leaks, them to stop running, etc.
When the filter is properly functioning, all air is expelled from the system in the first 30-60 minutes. If you still have air after 60 minutes then something is probably awry.
0) turn off the filter
1) check the intake fittings and make sure there is nothing loose that is allowing in air. Sometimes the cap is not on right, or the extensions to get the intake into the tank are not tight enough.
2) unhook the quick disconnect. Have a towel as sometimes is has some pressure and sometimes water spits out from the canister. Leave it disconnected just like if you were cleaning the thing.
3)undo the top and carefully put it back on. (Sometimes the seal is just not right)
4) put the quick disconnect back in (sometimes that seal is just not right either)
5)let it sit for a few moment
6) turn it on again
I’ve found that in just messing around with it in those steps.
Also, make sure the hoses and canister is situated as per the instructions. Sometimes a loop in the hose causes this problem.