Coast to coast overflow hampers wave?

banditpowdercoat · #1 01-25-2014, 01:05 AM

So I've been playing with my WP-25's on my 150. Have one at either either end. Got a not bad wave, or so I thought. Today, doing some spot feeding and such, Sump return off, so the water level in DT down below the coast to coast overflow. And now I am getting like double the wave size. And seems more sway in tank. Wondering if I should block some of the overflow off??? Maybe make it in 3 sections or I dunno, just be happy with the littler wave LOL

asylumdown · #2 01-26-2014, 06:25 AM

I'm no physics expert, but with the water level lower in the tank but the pumps at the same height, they'd be relatively closer to the surface, so to me that seems like you'd see more of a wave. Hopefully someone who actually knows the physics of liquids will chime in and tell me I'm an idiot, but when you've got a powerhead angled horizontal to the plane of gravity under 7 or 8 inches of water, you barely see any surface disturbance, but when that power head is only 2 or 3 inches below the surface of water, the surface turbulence is enough to create splashing.

I also know with a standing wave the whole mass of water is moving, but I still feel like the total mass of the water in your tank, relative to the output of your powerheads, will affect the kind of wave you develop. With less water in your tank, it seems like it would be easier for the powerbeads to create a bigger wave.

The C2C is probably affecting it somewhat, because as water flows over it, it's also taking some amount of kinetic energy from your wave with it, but any overflow will likely do that.

Not sure which of those things contributes more to what you're seeing, or if it's something else completely and I just don't know what I'm talking about.

Slick Fork · #3 01-26-2014, 06:42 AM

Coast to coasts and corner overflow boxes do dampen waves considerably since they cut them off at their "height". You could play around with covering the ends and see if you can get a result you like that still allows for decent flow through your overflow.

Wheelman76 · #4 01-26-2014, 06:56 AM

The closer to the surface your pumps are the easier it is to for them to create a big wave.

Jaws · #5 01-26-2014, 01:58 PM

Quote:

Originally Posted by Slick Fork

Coast to coasts and corner overflow boxes do dampen waves considerably since they cut them off at their "height".

Do you think that decreases the wave under the surface as well or just what's visible to us on the surface?

Slick Fork · #6 01-26-2014, 03:36 PM

I think it decreases the energy level of the whole wave. If you think of the way a wavebox works when there's no overflow to deal with, it goes back and forth like a seesaw. If you cut off the top of the cycle, you lose out on all the extra energy that would be gained on the "downstroke". Real waves seem to be less about current and more about momentum, if that makes any sense. A center overflow is ideal because the wave in the middle of the tank doesn't really move up and down, almost like it's a fulcrum point.

mike31154 · #7 01-26-2014, 04:34 PM

If you look at it from a 'head' pressure perspective, it seems logical that with a lower water level (less head pressure), the pumps are able to create a larger wave since they're moving less water. Not sure the overflow has that much to do with it, but I'm not a physics professor either!

When I first got my MP40s, I had fun playing around with the wave making feature, but am now content to have them run in a random mode. I only put them into wave mode shortly before I do water changes these days. Helps transport nutrients. Wave mode gets too noisy & annoying to use continuously. Livestock doesn't seem to care either way.

jason604 · #8 01-26-2014, 06:14 PM

Quote:

Originally Posted by Slick Fork

I think it decreases the energy level of the whole wave. If you think of the way a wavebox works when there's no overflow to deal with, it goes back and forth like a seesaw. If you cut off the top of the cycle, you lose out on all the extra energy that would be gained on the "downstroke". Real waves seem to be less about current and more about momentum, if that makes any sense. A center overflow is ideal because the wave in the middle of the tank doesn't really move up and down, almost like it's a fulcrum point.

+1

jason604 · #9 01-26-2014, 06:16 PM

How long is your 150g tank? I was thinking about getting the new WP14000 (upgraded version if the wp40)power head for my 75g 4' would that be overkill even with a variable power suppy?

banditpowdercoat · #10 01-27-2014, 01:33 AM

My tank is 5'. Amd I think 2 WP25's isnt enough, but 2 40's might be to much at full? Not sure. I have them running off a Apex, not the Jebao controller. I might upgrade to 2 40's later. If I ever find some extra $ that this Divorce doesnt suck out of me