Tropical Fish Keeping - Aquarium fish care and resources

Tropical Fish Keeping - Aquarium fish care and resources (
-   DIY Aquarium (
-   -   Eclipse 6 Flow Diverter (

Tyyrlym 01-05-2009 08:37 AM

Eclipse 6 Flow Diverter
Since starting my betta tank at work I've noticed an issue with my tank. The Eclipse 6's filter is a powerful one and the return stream of water knocks my betta around whenever he swims near it. My attempts to slow the flow with restrictions on the intake and output only resulted in a pump tripping due to overheating and a biomax pellet jamming the biowheel. Seeking a more permanent solution I decided to add a flow diverter to the filter. The principle is simple, put the diverter in such a place that it absorbs most of the flow's energy and redistributes it. Simple right? Well not so much, because of the design of the Eclipse filter there's not really a good place to put a diverter. The one obvious place, siliconing something to the front of the biowheel chamber, wouldn't do much as the flow is primarily vertical so a horizontal diverter is needed. Unfortunately the bottom of the outlet is curved and small making attaching something to it almost impossible. After staring at the filter for a while it came to me. Attach the diverter to another, remote, portion of the filter and extend it over to the outlet.

The reservoir between the filter pad and the biowheel as one large expanse of flat plastic upon which to work and unlike so much of the Eclipse filter clearances weren't tight. It's not perfect because the bottom of thereservoir is slightly higher than the outlet but its close enough. The force of the water exiting the filter is also low enough that I'm not worried for the structure of the filter itself. Mounting a diverter like this will also put no strain on the filter pump and hopefully I won't have to deal with another trip.

So here's the actual DIY portion.

Difficulty: 1 Out of 5. If you have even a passing familiarity with the use of a ruler and a drill this will be no problem for you.

Cost: Materials only, about $5 to $6.

Parts List:
2 Nylon bolts or screws 1/4" x 1"
4 Nylon washers 1/4"
2 Nylon nuts 1/4"
1 Piece of plastic 4"x6"

Flat head screw driver
1/4" Drill w/ 1/4" drill bit
Box cutter

I chose nylon bolts because they're cheap and non-reactive. There's no great load being placed on them so their low strength isn't an issue. If you really want you can purchase stainless steel hardware but there's no real point. Also if you absolutely have to have your diverter perfectly level you can buy more washers. The piece of plastic is up to you. If you do what I did and not try to level things then make sure that it's flexible enough to bend a little without breaking, but not too flexible, it needs to resist the flow and divert it, not get bashed out of the way. I bought a piece of PVC gutter material myself.

Step 1:
With the filter out of the tank, can't stress that part enough, locate the portion of the reservoir below the filter pad. It's approximately 2 1/2" by 1 1/2". On the long, 2 1/2", axis of the compartment measure in 1/2" from each side and mark a point on the center line. Drill a 1/4" hole at each point. The plastic of the filter is hard but thin, a good drill will go through it in a heartbeat. Make sure when you do this that you've taken precautions against the drill going through and hitting something.

Step 2:
Use your box cutter to trim your plastic to size. My own diverter was 3 1/2" by 5". You can get artistic with it if you want. The only real requirement is that the plastic extend out in front of the filter discharge enough for the flow from it to hit the diverter.

Step 3:
Either using the existing filter holes as a pattern (my method) or with careful measurements mark the positions of the bolt holes on the diverter and drill them out. I highly recommend using the holes in the filter as a pattern. Measurements are nice, but if you've already got an exact guide just use it.

Step 4:
Put the bolts through the holes in the filter, add the washers beneath it, slide the diverter in place, then put on the nuts. They only need to be finger tight, use the screw driver to hold the bolts while you tighten the nuts down.

Step 5:
Cut off the excess length of bolt.

Step 6:

As I said, if you want to you can get creative with it and mess with the size and shape of the diverter, I've got a few ideas of my own. Since the diverter itself is mounted with only finger tight bolts its easy to remove it and replace it with a new design. If you're really worried about securing the plate you can also add a third bolt in the compartment just prior to the biowheel.

After installing the diverter I saw an immediate improvement in my tank. Previously the flow out of the filter had enough force to drive my betta from the surface half way to the bottom of the tank if he swam into it. Now he can swim in front of it with barely a ripple. Total flow through the filter remains unchanged so it can still do its job, only the way the water reenters the aquarium is any different.

Tyyrlym 01-06-2009 01:54 PM

A small update.

I am not happy with this diverter plate design. It prevents a big downward flow directly off the filter but does nothing about horizontal flow. I'm currently pondering a modified design that will take care of that as well. I may have to get fancy with the silicone though. I'll keep this thread up dated.

aunt kymmie 01-06-2009 03:24 PM

Yes, please do! My diverter is a cut out piece of plastic water bottle curved around the outflow with a bunch of guppy grass in front of it. It seems I'm constantly shoving the grass back up under there. I'd like something that wasn't so "MacGyver". :-)

Tyyrlym 01-16-2009 09:23 AM

As I mentioned earlier my original diverter was working, just not as well as I wanted it too. The simple plate prevented vertical flows but only seemed to encourage a rather nasty horizontal current. So, I went back to the drawing board.

First, I used a larger section of plate, 6" x 4". Next, I scored the edge of the plate and bent it up to give me a 3/8" lip all the way around. Then I drilled 3/32" holes all across the plate. Finally I bent small strips of left over material into chevrons and glued them to the plate. Its a lot more elaborate than my first attemp but it works INCREDIBLY well. I attribute most of the effectiveness of the diverter to those two chevrons right in front of the outlet. The immediately slow and break up the flow. The large plate, holes, and raised lip just finish the job. My betta has swum directly infront of, below, and behind the diverter with no ill effects, no getting blow around, anything.

Oh, due to the increased size of the diverter plate I added a third bolt to hold it in place.

aunt kymmie 01-16-2009 11:39 PM

Tyy- that's a great design. I've got the same tanks ( 2), same problems. One betta loves the flow (go figure) but the other one hates it. I want to do the exact same thing. What type of "plate" is that and where do I purchase? Hardware store I'm assuming...

Tyyrlym 01-20-2009 06:18 AM

It's a piece of PVC rain gutter actually. Pretty much any piece of plastic that is non-reactive (PVC or HDPE) and has no additives like fungicides in it will do so long as it's big enough and is strong enough to not bend and flex in the water stream but still thin enough to work with will do.

Tyyrlym 07-22-2009 06:50 AM


My modified diverter is still in service. I'll admit I had some doubts as to whether the chevrons would hold up in the flow but they are doing just fine. The only mod I would probably do is to make the holes I drilled larger. Because of the position of the plate close to the light algae build up on it can get pretty bad and it can start to clog the holes. I keep it wiped down but with slightly larger holes, maybe 1/8" or 5/32", it might not be an issue. I may have to bring my drill to work one day, take everything out and do the mod.

Oh, one nice side benefit of the diverter is I can refill my tank after a water change without disturbing the sand at the bottom. I just pour the new water into the filter and the diverter sends it down into the tank in nice, small, broken up dribbles.

All times are GMT -5. The time now is 09:47 AM.

Powered by vBulletin® Version 3.8.8
Copyright ©2000 - 2017, vBulletin Solutions, Inc.
vBulletin Security provided by vBSecurity v2.2.2 (Pro) - vBulletin Mods & Addons Copyright © 2017 DragonByte Technologies Ltd.
User Alert System provided by Advanced User Tagging (Pro) - vBulletin Mods & Addons Copyright © 2017 DragonByte Technologies Ltd.

For the best viewing experience please update your browser to Google Chrome