How to Prime a Filter
Planted Tank Forums
Your Tanks Image Hosting *Tank Tracker * Plant Profiles Fish Profiles Planted Tank Guide Photo Gallery Articles

Go Back   The Planted Tank Forum > Specific Aspects of a Planted Tank > Equipment

Thread Tools Display Modes
Prev Previous Post   Next Post Next
Old 02-01-2004, 04:02 PM   #1
Wannabe Guru
PTrader: (0/0%)
Join Date: Oct 2002
Location: Houston, TX
Posts: 1,614

This is a repost of part of another thread going on now, I think that the topic deserves it's own heading so I'm beginning anew.

Many people choose to fill the canister with water before reconnecting, in the hopes that excluding that air will make start up easier. This does not solve the problem for typically a bubble will be trapped below the valves and the bubble rising in the inlet line breaks the siphon or get trapped in the impeller and airlocks the filter. Most importantly, this method ignores the physics involved.

The whole thing to priming is to be sure the air is expelled the right way, through the outlet side of the filter, not up the inlet which will break your siphon. How much air is expelled is not important, as long as it moves the right way. That can be done, as was said in the other thread, by connecting the waterfilled inlet lines to the canister and letting air out the outlet side of the filter until water has filled the filter and runs out the outlet (have a towel or bucket handy.)

It can also be done by having the outlet tube completely empty of water when the unit is reconnected, but be sure the in-tank outlet/spraybar is above (or alt least very near) the level of water in the tank so air can escape. The weight of the water in the inlet tubes will assure you that no air can move up the inlet line, water will flow down that tube, air up the other. If both tubes are dry, perhaps you just cleaned the tubes, connect the inlet taps, suck on the filter outlet tap just to get water flowing into the filter then connect the outlet tubes before the filter is full, all the inlet side is full of water which is heavy, so air must go up the outlet. When rushing water stops you turn on the filter. If the inlet tube is still full, perhaps you bled water from the lines to clean them and the outlet is empty but the inlet is full, then simply connect all tubes, open outlet taps to allow air flow, then open inlet taps to begin water flow. Again, when the water stops rushing, turn on the filter.

I cut the &#%$@% out of my hand rocking a Fluval 303 trying to get it going following that bad advice to first fill the filter with water. I spent an hour on the stupid thing, running late for an appointment by then, and while rocking the filter to try to get the air out my knuckle hit the sharp glass edge of the lower tank. It bled a lot, a real gusher. So I finally had to sit and think about why it was so difficult. Looking that physics of the thing, it becomes obvious -- you gotta get the air to go up the outlet. Either bleed it out, past the impeller by letting air, then water, escape the canister from the outlet side, or have the entire oulet line full of air so that it all has to go up with water pushing it from the inlet.

So, for units that have the integrated taps but no self priming, you might need to bleed all water from the outlet line -- I have begun doing this as part of my procedure, it flushes a lot of crud from the lines that otherwise can flood into the tank and it gives me some tank water in my bucket to rinse media in.

I find that the instructions on the canisters I have show pictures of the outlet lines (spray bars) above the water level of the tank when starting the filter, but they don't state that is necessary for air to get out of the system. Even the self-priming units can have difficulty if the outlet is below water when starting up if air needs to get out of the system.

If you are having trouble starting a canister -- look to the path the air is taking. It is the key.
anonapersona is offline   Reply With Quote

Quick Reply

Register Now

In order to be able to post messages on the The Planted Tank Forum forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.
User Name:
Please enter a password for your user account. Note that passwords are case-sensitive.
Confirm Password:
Email Address
Please enter a valid email address for yourself.
Email Address:
Your Location. As precise as you feel comfortable with.
Security Question
While balancing on a piece of wood, two inches by four inches known as a 2x4, John and his friend Sally both spotted a dalmatian inside of a truck with sirens. The animal with John and Sally is a _ _ _?
Please select your insurance company (Optional)


Human Verification

In order to verify that you are a human and not a spam bot, please enter the answer into the following box below based on the instructions contained in the graphic.

Thread Tools
Display Modes

Posting Rules
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
Undergravel filter : Am I crazy? Ianice Berg General Planted Tank Discussion 5 09-10-2004 09:12 PM
How to prime a canister filter? GraemeK Equipment 4 08-31-2004 02:56 PM
Mod. a H.O.T. Magnum/diatom filter....? fedge Equipment 28 08-30-2004 12:00 PM
Woodshrimps and Diatom filter macbrush Equipment 6 07-21-2004 01:08 PM
Undergravel filter and large rock question. oe254 Equipment 18 01-02-2004 03:07 AM

All times are GMT. The time now is 08:44 PM.

Powered by vBulletin®
Copyright ©2000 - 2015, Jelsoft Enterprises Ltd.
Copyright Planted Tank LLC 2012