Can't Rid Magnum of Bubbles, Will This Affect LR?

[nsu7]

Recently I posed a question about venturi in FO and I went back and didn't see anything about whether or not it will hurt LR. If I can't rid the Magnum of this unintended venturi effect, will this negatively affect LR (am looking to slowly add 110+lbs)

I re-read the Magnums manual and there are no obvious problems as to why air keeps entering the canister. The top of the canister is below the tanks water level, there are no obvious air/water leaks in the tubing. Perhaps it's residual bubbles from the coralife 220 superskimmer diffuser or needlewheel intake pump?

Does anyone have any insight into stopping the air entry into the Magnum?


TIA

 

[greenmaji]

A sponge pre-filter for the magnium's intake...?

 

[steve-s]

Something is most likely not seated correctly within the canister. This will more commonly cause cavitation and the resulting airbubbles. Disassemble it and place each piece back carefully inspecting as you go to ensure there is no foreign debris preventing the internal filter casing, impeller or lid from seating properly. Also make sure the intake/outflow hoses are seated correctly and not jaming down on anything internally. You can also try rocking it back and forth gentley while in operation, it will often dislodge air pockets that will keep the cavitation going.

Cheers
Steve

 

[nsu7]

Ok, I'll check those things. On a lesser note, in general will air bubbles harm LR?

 

[saltcreep1025]

If you look under the rock and see pockets of air those could eventually kill off whatever they are covering.

 

[nsu7]

No, I don't have a sponge for the prefilter, the sponges are on the powerheads. [/quote]

 

[nsu7]

Steve, Thanks, there was a large amount of tiny carbon free floating in the canister(so much for Marineland's claim at evenly sized carbon). I cleared them out and switched to the tri-based pellitized carbon I bought from memory doctor (identical size pellets).

I think I figured out where most of the air was/is coming from, air stuck in the "u" elbow and that the tube on the intake connected to the quick release valve was not truly seated right (as it wasn't an even cut). So I fixed that as best I could. I believe that since the canister is not on ground level there's not enough pressure to properly burp the the canister so air is sitting in the "u" elbow of the intake. I got most of it out doing repeat burps and completely submerging the intake stem, relocking the valve, and keeping the other end submerged as I reattached that half of the quick release intake valve to the canister.

This reduced much of the bubbles that were visible, coming in from trapped air in the elbow. Now I suppose I need to (with the unit off...) pull water through it backwards (w/ PH) to completely expell all the air.

Just when I thought I was reducing head pressure and maxing my GPH by elevating the canister 2 feet off the ground it backfired by keeping back syphon pressure (I think ???) low so that the unit will not completely burp.