PDA

View Full Version : DIY Flow diverter/diffuser


Sarkazmo
05-29-2009, 12:29 AM
I've noticed that several people (like myself) are looking at ways of limiting the current (from HOB filters) in their tanks so as to not stress the fish and plants. Lots of different ideas have been tossed around from limiting water intake to using a rheostat to slow down the impeller in the pump... but I think you'll find this quite a bit easier and pretty much for free as most of you probably already have everything you need to do this little project.

Supplies needed:
20 OZ (591ml) Life Water/Gatorade style thick plastic bottle
Shears or heavy duty scissors
Box Cutter or Sharp Knife
Emery board or sand paper

That's all ya need!

[Only Registered Users Can See Links.]

First you need to remove the label from the bottle and wash the inside AND outside of the bottle.

MAKE SURE THAT YOU RINSE MANY TIMES TO REMOVE EVERY TRACE OF SOAP!!!!!

If you want to remove the label glue you're going to have to fill the bottle with very hot water, cap it, then scrub the glue off the outside with, again, very hot water and an abrasive kitchen scrubber.

If you don't want to bother with the glue you need to plan your cuts on the bottle so that the glued area is the part that goes over the rim of your tank so it's not in the water.

[Only Registered Users Can See Links.]

Now that it's clean it's time to section the bottle into three pieces. Check out the pic below. Find two ridges on your bottle, one near the top of the side of the bottle and one near the bottom. Using the valleys on the bottle will allow you to cut a straight line with your box cutter/knife and also the slight curving into the valley will give the diffuser the strength to keep from distorting from the flow.

[Only Registered Users Can See Links.]

In my case I didn't want to scrub off the glue so the cut you need to make from top to bottom is right along the right edge of the glue. This edge is folded back twice upon itself. Now there's no hard set rule on wide to make these folded over areas and is based on how thick the rim of the tank is that you'll be using it on. I tend to just make them about 1/2 an inch and just eyeball it.

[Only Registered Users Can See Links.]

Use your shears to round any sharp corners and such. Use the emery board/sand paper to smooth all edges that've been cut. This is a very important step as you don't want your more inquisitive fishes from injuring themselves on sharp edges. Sancho, my betta, actually goes into the diverter and 'plays' in the current.

Some people put put some gravel in the diverter to act as extra material for you bio filter to load up. You could put phosphate remover in it, or peat. I wrapped a chunk of Java Moss around a bit of lava rock. This works out great for me as the moss drags at the water flow slowing it greatly plus the moss gets first dibs on the nutrients in the water.

Now you may think "this can't work all that well" and it's good to question but here's a video that shows just how well this little thing works. This is my 1.5 gallon tank that's being filtered by a Marineland Penguin 100 Bio-Wheel filter. At it's best flow rate, the entire volume of water in the tank is being filtered about once every minute.

[Only Registered Users Can See Links.]

If you want to diffuse the water more you can drill small holes in the diverter. But a word of warning! If you do this you have to make sure that EVERY hole been deburred or your fish could easily get cut!

You can use .5L water bottles instead but the plastic is VERY thin and may not hold up over time.

I hope that this has been helpful to you all. I do not take credit for coming up with this general idea but I do believe that my version is superior to all that I've seen.

Sark

korith
05-29-2009, 04:01 AM
Nice, seen lots of tutorials about making these. But I think your the first one to mention needing to get rid of the sharp edges that the fish may poke into.

Wiggs
05-29-2009, 04:05 AM
Great info, thanks for posting it up. I'm sure it will help a lot of people as I've seen the topic come up a few times recently.

Gayle
05-29-2009, 04:06 AM
That was very good!!! Well done!!!!

Northernguy
05-29-2009, 04:10 AM
That'll work! Nice one!

Fraoch
05-29-2009, 01:12 PM
Wild Turkey mentioned this earlier but I haven't seen the rounding of the edges either, thanks!

I also haven't seen putting gravel in it, java moss or the requirement to remove the glue.

Sarkazmo
05-29-2009, 07:11 PM
Thanks guys and gals! I hope it's of some use.

I found out the hard way about rounding off points and sanding edges. Sancho got in a diverter I made to play in the current and got his fins shreaded. :(

But he's all healed up and doing great and still loves to play in the current. :)

Sark

Sarkazmo
06-03-2009, 02:21 AM
I'm happy to say that the exact one seen in the photos above is in use on my new 10gal female betta tank: [Only Registered Users Can See Links.]

Coco4Pr3z
06-15-2009, 06:04 PM
Great write up. I just built one for my 10 ten gallon and it works much better then the sponge I had on the end of it before. Thanks. thumbs2:

KingFisher
06-15-2009, 06:08 PM
Great idea and you can't beat the price! thumbs2:thumbs2:thumbs2:

reds_21
06-23-2009, 03:32 PM
i checked out that video, but is there anyway that someone cast post some pics of this installed and working? id like to get a better look at it installed and details on what its hooked to

Sarkazmo
06-23-2009, 07:26 PM
i checked out that video, but is there anyway that someone cast post some pics of this installed and working? id like to get a better look at it installed and details on what its hooked to
It simply hooks to the tank rim and the HOB filter sits on top holding it in place. No adhesives needed, just gravity. :)

Here's a simple illustration that I've made. This is a tank from the side and I think it's pretty much self explanatory. The diverter will be mostly submerged. As the water spills out of the HOB into the diverter it swirls using up a lot of the flow's energy. The water then diverts out to the sides causing more surface agitation than the filter would on it's own. This has the effect of helping with the oxygenation of the water as the turbulence at the surface causes more oxygen to become disolved into the water. Not a bad side effect. :)

[Only Registered Users Can See Links.]

Sark

PS: Here's another video of an earlier version of the diverter but still the same principal. [Only Registered Users Can See Links.]

reds_21
06-23-2009, 08:21 PM
i see whats going on now, thank yo ufor that. i will definitley do this. as for the intake tube, what kind of media can you stuff in the bottom portion of the tube to lessen the intake pressure? i notice whn i feed the fish, most of teh food goes right in to the intake. (wasted food)

Sarkazmo
06-23-2009, 10:27 PM
i see whats going on now, thank yo ufor that. i will definitley do this. as for the intake tube, what kind of media can you stuff in the bottom portion of the tube to lessen the intake pressure? i notice whn i feed the fish, most of teh food goes right in to the intake. (wasted food)
I think that you'll see a difference when you get the diverter installed. It changes the currents in the tank so the food will go elsewhere. If it's still a problem you can use a prefilter sponge but the food will still get sucked toward it. The food just won't go into the filter, it'll stay on the surface of the sponge. Most people use these sponges to keep small fish, fry, and shrimps from getting sucked into the filter.

Here's a listing for the prefilter sponges on ebay, you can probably get them elsewhere though: [Only Registered Users Can See Links.]|66%3A2|39%3A1|72%3A1205|240%3A1318|301%3A1|293%3A1|294%3A50 ([Only Registered Users Can See Links.])

Sark

reds_21
06-24-2009, 12:32 AM
awesome, thank you sark!!!

Fraoch
06-24-2009, 01:52 PM
i notice whn i feed the fish, most of teh food goes right in to the intake. (wasted food)

You can also use a floating feeding ring to keep food in place, provided the food also floats for a little while.

Wild Turkey
06-24-2009, 02:08 PM
Very cool, some new twists on an idea and a great article.thumbs2: Now i have something to refer ppl to thats on site when i say "the soda bottle trick" and they come back with "..what..":hmm3grin2orange:

King Tut
06-25-2009, 12:59 AM
This post helped me immensely. I was able to adapt the Soda Bottle to work on my 2 Aqueon 55 HOBs. I needed to divert the flow for the Angel I am putting in there. I made mine to attach to the HOB Cover and then slide all the way under the fliter coming up behind it. It leaves a smaller space for the fish to try and get in there. I am looking at using some plastic screws and nuts to attach this and make it a little more aesthetic. May even silicon the nuts to the cover so I don't have to worry about them falling off. Thanks for the inspiration.

Sarkazmo
06-25-2009, 01:29 AM
Excellent! I'm so happy that this thread is helping people out. :)

Sark

Sarkazmo
11-16-2009, 03:32 AM
I was doing tank maintenance today and figured it was a good time to get a pic of the above described diffuser. The diffuser's been in use for several months now and Sancho's still happen with his lack of being blasted around by the filter output.

I put Java Moss on a bit of lava rock to help the diffuser do it's job. This also has the added benefit of all the water passing through the moss and being filtered by it as well. Some time ago I removed the bit of lava rock as the moss'd grown to the point of being able to withstand the flow without need of the weight of the rock.

Here it is today. The water's low as I was doing a water change but you can see how the moss has grown from all the nutrients. It's increased volume is also helping break up the flow just that much more. The weird thing is that the moss has actually grown to the plastic of the filter!!!

Sark

[Only Registered Users Can See Links.]

Kazenouta
01-10-2010, 04:28 PM
Sorry to bring back out an old thread but, I just wanted to say thanks for posting this build on the forums. I just completed a flow diverter for my 5 gallon Betta tank and the difference was instant.

Thanks a lot!thumbs2:

AndyD
01-30-2010, 04:59 PM
Very cool. I will have to build one as well.

I usually turn off the filter for 3 minutes when I feed to let them eat in peace. I was thinking of building a small control module with a button that has a 3 minute timer and hit it once when i feed then i dont have to wait around to turn it back on.

But this makes a lit more sense.

AdrienDeLaChicago
09-06-2010, 01:51 PM
I do not mean to sound atrociously disrespectful but I could not have the appearance of some plastic bottle hovering at the waterline of my tank. It reminds me of the garbage and waste that our oceans are forced to harbor due to human waste and littering. It is not aesthetically pleasing. Why go through the trouble of creating something beautiful for your beautiful fish to have something that looks like garbage floating on the top?

Would not a sponge filtration system work better AND look more attractive?

Sarkazmo
09-06-2010, 02:38 PM
With a clear bottle it's nearly invisible. It's a solution to the problem at hand, not a solution for filtration as a whole. The simple thing would be to go buy another filter that does exactly what you want it to, IF it exists. This is about adapting what you already have at hand, not purchasing more goods, causing more waste of materials, energy, and time. It's recycling a product that was going to the dump. If you have issues with that then that's your issue, not mine. It works, it works great, it's easy to make, and it's helped a lot of people keep their fish in a healthier environment because they don't have to fight the extreme currents any longer but their tank is getting much more filtration than needed providing the cleanest water possible. Yeah... I think I'll keep my nearly invisible flow reducer.

Sark

HeatherB
09-06-2010, 06:21 PM
I need to make some of these! I better go buy some Gatorade bottles!!

AdrienDeLaChicago
09-07-2010, 06:10 AM
Once I wedged a clear piece of hard plastic I cut from flat sided plastic storage container to wedge into the exhaust of the filtered water that was exiting my Aqueon 10 gallon HOB filter. The plastic I used was at the water line and was horizontal. It was a flat piece of plastic that "was" invisible. I basically wedged it into the opening and it made a huge difference in the water floor and you could not see it at all.

promise
09-19-2010, 06:32 PM
Finally an idea i can use to stem the flow from my filter in my 10, its displacing the sand and the Betta Hates the force of the flow

Thanks Sark great write up and an excellent idea :19:

rtbob
09-23-2010, 02:38 PM
Great idea! Can't wait to try it.

HeatherB
09-24-2010, 12:28 AM
I made 5 in just the last week or so.

I have been drinking Gatorade like no tommorow!

kflynnigan
09-24-2011, 02:20 AM
I like your idea...does this also decrease the suction from the the part that sucks the water in?

genocidex
09-29-2011, 08:09 AM
no it wouldnt, this is to reduce the surface agitation to help keep co2 in the tank for a planted tank. if you are having issues with fish getting sucked onto the intake then your filter is too strong, you can add a sponge prefilter if you want im think that will help