Diy: Chaotic Turbulance On A Budget

[RipSlider]

I've been doing more reading about how I want to set up my new salty tank, and one thing that I have learned is that chaotic, changing flows are better than solid streams of water for a reef.

So, I had a look at some of the systems that allow you to do this, and when I had picked myself up off the floor having looked at the prices, I wondered if I could DIY something.

I saw the "dump" device that acts like a toilet cistern, but that doesn't really fit in with what I want. I want something that is quiet and small.

So I got to thinking about the following:

<please note, grovelling apologies in advance, I am dreadful with Sketchup, so diagrams will be available as soon as I learn RealCAD in the next few days>

Imagine that we have two balls.

One is large and hollow, like a tennis ball, but smooth on the outside.
The other one is small and dense, like a large marble or something heavier.

We cut the large ball in half, right along it's middle. In one half we glue the hard ball in the middle of the hemi-shpere.

Then we drill a number of 1mm holes at random points throughout the sphere. We also cut out a three large holes in three random places.

We use a one of the large pieces of plastic to make a sort of wedge shape inside the half with the marble in it. < this will be a LOT clearer in the diagram >

We then glue the two halfs back together.

We then butcher a T-section or X-section of stiff junction for pipework by splitting it down the middle. We drop our device into the middle of the junction and glue it back up again.

We then plumb this, in what ever way, into our system. One arm is connected, either the cross piece in the T-section, or one of the four tails in the x-section to the flow from the filter. The other sections lead to outflows back into the tank.

We then push water through it.

What happens?

The ball will act, because of the weight and the small holes, chaotically. It will spin, tumble and turn in every way possible, and never fall into a pattern.

A tiny fraction of the water hitting this junction will be used to move the ball.

The vast majority of it will look for the path of least resistance. This will be through the three big holes.

In the tank, this will lead to a completly random pulsing of the current. This random pulsing will set up random flow movements in the tank, making everything happy and jolly. Note that this would only work if there were two or more inflows into the tank.

All this is driven by a single powerful linear pump, and could be probably be built for about £20.

I'll be building of of these into my plumbing, so will add photo's in the future, and add diagrams as soon as possible.

If it does work, I reckon I've just saved myself around £600 easily, maybe £1000 odd as I will have a big tank and might need two. If it doesn't, I've lost an hour of my time and 6 doubles at the pub.

Things I need to work out though before completion:

What the small ball is made of
what the best shaped baffle will be in the big ball and how big
how to keep a nice, easy, low friction movement happening. Thinking that carbon will be the answer to this.
How to maintain it when it does start to stick.
How close the tolerance needs to be with the ball and the junction. Too lhigh and it will stick easily. Too low and it will rattle, which spoils the whole idea.


Steve

 

[Aquascaper]

Nice idea, my only concern would be the maintenance of a sealed component. If it jams what do you do? I can only think of salt build up or particle ingress as a cause and I supose removing the component and flushing it with hot water would solve most of those issues

Another option would be to just buy a couple of 4-way wave timers and put 8 powerheads onto them, not quite as random but still effective.

 

[RipSlider]

Yes, definately need to work out the maintaince part.

I COULD use 8 powerheads and a wave timer, but this is going to be a lot more money than £20. It was the cost of wave timers/tunze's ect that made me so upset in the first place.

However, if it turns out that the above isn;t practical, I'll have to cough up the money. No sense in not trying though.

Steve

 

[SkiFletch]

Hummm. That sounds neat but my poor pea sized brain can't visualize it

I'd been tossing around a similar idea to yours I THINK, but I'd love to see a picture of what you're envisioning here

 

[superman]

In tanks under about 75 gallons you can do multiple maxijet powerheads with the nozzles cut off. Maxijet powerhead impellors spin in either direction, so when you have a nozzle cut off and turn the powerhead on and off you will notice that it will change periodically the direction of flow. Putting 1 or as many as needed on a timer(s) you can get some awesome random flow on a very low budget. I have 4 of these in my 37 gallon cube tank, and the random flow patterns were incredible!

 

[Aquascaper]

Your idea sounds really cool and I can visulaise it as various similar ideas have sleeted through my brain at one time or another but i've just lacked the motivation to follow them through.

As you say, if it can be done for under £20 do it but if not a wavetimer barplug would be the next best option IMO.

 

[crazyelece]

I would think a SCWD would be cheaper and less time consuming and the downfalls to both your idea and the SCWD are the same. Sealed units are a pain to fix after they stop working and there is a tremendous amount of backpressure and thus loss of flow through them due to the added head to the pump.

How big is the tank? If you are looking at adding two of these to make it work, I would recomend an Oceans Motions Sea Squirt 4 way.