Any ideas on the Holy grail: a DIY wavemaker?

apos

Member
I'm interested in a brainstorming thread!
The goal here is to think of a simple, ingenious design for a device that will route water (ideally from a return pump without any extra pumps) such that it switches directions at a reasonably decent rate (every 10-20 seconds at the longest, every 2 seconds at the fastest) that is easy enough that folks can DIY it themselves. I think this is sort of the holy grail of DIY "ocean fl"ow projects.
Essentially the problem is to build a unit that oscillates water back and forth like the ocean, but doesn't involve the basic "several powerheads cycling on and off on a timer" concept. Not that that isn't a good solution on its own. But many of those systems are ultra expensive in their own right, and a different sort of project/purchase.
Currently, there are several known designs I can think of:
1) WavySea/Seaswirl: motor rotates outlet
-probably the best overall effect, closest to real ocean movement
-lots of moving parts, gears, motors: high likelihood that any DIY, non-machined unit won't hold up very well over time
-non-waterproof electric parts/belt = DIY danger
2) Wavebox type 1: usually two openings at top of box and bottom, and the flow alternates between the two
-I don't have any clue how it works internally!
-also likely a lot of moving parts
-I assume that it moves the surface of the water quite a lot, which is not ideal for some setups. Be better if it moved side to side, but that might not be how it works
-theoretically seems like the best option for a DIY if there were some simple mechanism for it
2a) Wavebox type 2: basically an overflow with a powerhead at the bottom on an oscillator
-uses an extra powerhead, boo.
-major surface wobble: awesome, but a little scary
3) SCWD-like: basically, switches between two return outlets into the tank
-clogs, needs lots of cleaning
-severely reduces head pressure
-gear system unlikely to be easy to DIY
4) Gravity switching surge devices: basically two chambers that fill and flush/drain alternately
-gravity fed = low gph/pressure
-risk of overflow if there's a clog
-likely to create lots of bubbles (open to the air by its nature)
Can anyone think of anything other major category (again, non alternating powerhead based) I'm missing?
The focus of my brainstorming is on some sort of wavebox design fed not by an extra motor, but by the return pump feed itself: sort of an in tank SCWD/wavebox hybrid. The trick is figuring out how to eliminate the need for gears and lots of extra moving parts. There's a number of things I'd like to try and test out and play around with, and I'm scrounging up materials for play. When I get some things up and running, I'll document what will likely be a lot of at least amusing and instructive failures.
In the meantime, anyone else feel free to chime in with any idea, no matter how out there or unlikely: maybe it'll inspire someone else to find the real solution.
 

reefraff

Active Member
I've heard of a couple but never tried to build them.
On the cheap
get a piece of large diameter PVC with a

[hr]
on cap at one end. Drill a hole in the cap that you can push a piece of rigid airline tubing through it. Mount that in the tank with the cap side up. Zip tie a balloon to the tubing and

[hr]
the cap on the pipe. Run airline tubing from a pump to a T assembly and on to the rigid tubing sticking out of the top of the PVC. Put a valve on the open end of the T and leave it slightly open. Set the air pump on a timer, one of those strips that can be set down to a 15 second on/off cycle would work best. Pump turns on, balloon inflates and pushes water out the PVC. Pump turns off air is bled out of the valve, balloon deflates and water runs back into the PVC. Replacement blatters cost about 99 cents for 50 at the party store
Takes a little playing to get the timing and air valve settings right but work decent according to the guy that told me about it.
Along the same lines and much more effective is to do basically the same as above except you run an airline from a high volume airpump right into the PVC or acrylic chamber. On a T in the line you mount a solenoid. Pump runs constantly and every say 10 seconds the solenoid fires releasing the air. The guy that told me about this setup had it running on like a 210. He said it produced a big enough wave to feel it on the floor. He also said directing the air output from the solenoid across the surface of the water lowered his tank temp pretty well.
Depending on the budget either on of those systems should be doable for most DIYers.
 

apos

Member
get a piece of large diameter PVC with a

[hr]
on cap at one end.
What, does SWF sell PVC parts now, or did you use a dirty word? :)
Anyway, I'm not 100% sure I understand the setup you are describing. Is the wave action here due to water being pulled up above the water line inside the PVC and then dropped back down again via gravity once the pressure is released? If so, that sounds like a pretty neat design. I think I'd need to see a diagram to really get what is hooked up to what: I'm not quite seeing it right atm.
 

apos

Member
Originally Posted by 1journeyman
http:///forum/post/2512224
The Wave2k is a great wavemaker. I've got it. Sadly, I'm not talented enough to make one.
Yeah, I have to agree that this looks like the all around best simulation of wave motion you can buy. It's a pity that it's so complicated (well, it's not rocket science I mean, but it does have a lot of moving parts). While some people could definately rig something up that would have the correct motion (there's a youtube of someone that uses an oscillating fan motor), my main problem as a DIY super-solution is that unless you are really really good at machining parts exactly and to quality standards, a DIY version would break down or mess up alot.
 

apos

Member
Ok, so do I have this basic idea correct of how water is slowly pulled up and then dropped back down via gravity when the pressure releases?
Theoretically, two of these devices could be linked together on opposite sides of the tank: one pulling up while the other drops down, minimizing the surface wobbling/water volume change a little. Two screened exhaust nozzles added to increase tightness of flow a little as well as not pushing water straight down.
Hmmmm....
Now the question is how the pressure is built up: still have to figure out that balloon solution (I prefer not involving an electronic oscilator: that seems like cheating, but an air pump is certainly okay)
 

wattsupdoc

Active Member
Reefraffs deign is similar to the reverse carlson design. The baloon inflates and pushes water out. When it deflates water is drawn back into the pipe. Re-read his post.
 

apos

Member
I read it, I just still don't quite get it, or at least, that description is off. It's still the air pump that's pushing water out of the chamber, no?: and it would be doing that balloon or no balloon. And I don't get quite what is attached to what in the setup: the balloon goes onto the rigid tube sticking out of the pipe cap... but then the pump somehow is stuck on there as well, even though the only open of of tubing is now inside the pipe. I'm sure it works, I'm just not seeing how its all put together.
In any case, the balloon method sounds potentially a lot quieter, though I also can't see how a tiny valve for exhaust could create the huge push that the RCSD creates.
The RCSD, however, doesn't require anything eletrical switching on and off.
 

apos

Member
Played around with a prototype RCSD using just some pvc, a coke bottle with the bottom cut off and airline through the lid. Took awhile to get the heights of everything right, but it does work quite well for generating a nice volume-wide swell... and is indeed pretty noisy (toilet flushing noise). A great DIY for a wave action frag tank in the basement I think, but not something for a DT, in the end, unless you can get over the noise.
And on the balloon thing: wait-- is the balloon INSIDE the pipe, attached to the inner end of the rigid tube? That makes more sense if so, though I still don't see how it would create much sudden outflow/inflow.
 

apos

Member
Still trying to figure out how the balloon thing works...
And does anyone know a cheap way to pump air OUT of something, in order to lift water above water level in a tube? I'm trying to work out a system for lifting and then quickly dropping water in this way, but it requires pumping air out (and holding the pressure) and I don't know if any of the usual cheap pumps used in the hobby actually can do that. The only ones I know of are industrial, way too powerful, and incredibly loud.
 

wattsupdoc

Active Member
Put a maxijet 1200 in the DT. Connect tubing to it. Then connect to a container above the tank. Put the maxijet on a timer.
 

apos

Member
That's the sort of heavy moving parts/timer system I'm hoping to avoid though (basically the whole carlson surge setup).
I was thinking more along the lines of an upside down container mostly out of the water, with the air slowly being sucked out and thus pulling the water up into the container, after which at some point a seal would break and the water would fall back down into the tank. This works quite well with me doing the sucking on the tube, but no cheap/quiet aquarium air pump I know of sucks instead of blows. Also, it gives me a headache after awhile! :)
Vaccuum pumps are generally pretty darn loud and I'm not sure if they could really stand up to the pressure load of holding up water (which is fairly heavy after all).
 

snakeblitz33

Well-Known Member
How about this?

Water goes up into the acrylic chamber and then is expelled through a maxijet powerhead that is on a wavemaker. It rapidly pushes water out of the chamber, but not so much that it blows bubbles. When the pump turns off, the water rushes back into the chamber. It creates a wave motion in the aquarium. A maxijet 1200 can make a really good wave in a 125 gallon tank.
 

apos

Member
variation on 2a, yeah. I actually wonder how that would compare to the standard top overflow version in terms of the wave it generates. Of course, if you have a wavemaker already, then you have a wavemaker already. :)
The real tough part on these is attaching them sturdily enough so that it won't rip itself off or damage the tank. The Tunze versions basically come with a warning that they can rip a tank apart if its too weak.
 

reefraff

Active Member
Originally Posted by Apos
http:///forum/post/2512722
What, does SWF sell PVC parts now, or did you use a dirty word? :)
Anyway, I'm not 100% sure I understand the setup you are describing. Is the wave action here due to water being pulled up above the water line inside the PVC and then dropped back down again via gravity once the pressure is released? If so, that sounds like a pretty neat design. I think I'd need to see a diagram to really get what is hooked up to what: I'm not quite seeing it right atm.
The pipe is mounted in the tank. The air forces tank water out of the pipe and then when the air is released the water can rush back in..
 

reefraff

Active Member
On the balloon thing and this works basically like the reverse carlson. The ballon is zip tied to the rigid airline. that is what feeds the air into the balloon. You put the balloon into the PVC and that unit mounts under water. When the balloon inflates it displaces water with air. It would be like placing a gallon milk jug full of air in your tank and pushing it below the water line. The Reverse Carlson setup just uses air instead of a bladder (Balloon).
 
Top