Random Alternating Flow

[wkada]

I'm pretty much done with my tank upgrade and am looking to add some SPS for the first time. Have been reading that you need high flow as well as "random alternating flow". I think I have the flow (upwards of 2500gph in a 65g tank with koralias and the return pump), but it is constant. Does the coral really care if the flow is one way or back and forth? Is there any hard data to support the use of wavemakers, etc. Seems like you would have to set up identical tanks with identical flow, one alternating and one not, then observe the coral growth for years to really see if there were a difference. Looking for answers before shelling out $400+ for a Vortech pump.

[SoLiD]

Personally, I love Tunze Waveboxes. IMHO There's nothing else like them. Not even Vortech... :wink_smile:

http://www.youtube.com/watch?v=o9fDqdTu_Z0

[BIGBIRD123]

I agree, but come mid-March, I'll have a Tunze wavebox and 2 Vortechs that will ROCK the water in my 280g. WOOOOHOOO!

S

[chark]

Wave boxes are great. But you would be fine without it. If the pumps are in the right place it should be fine for sps.

[wkada]

thanks guys, I think I will stick with what I have currently and forego the high dollar gadgets for now. We'll see what happens.

[SoLiD]

I tell you what. Buy a Tunze Wavebox and You'll see why so many people have them and love them. They always get sold very quickly in the "For Sale" forums on Reef Central.

:wink_smile:

[wkada]

will be on the lookout for a used one

[ErikH]

The regular sized waveboxes are not made for tanks shorter than four feet.

Place your powerheads so the flow hits each other. This will create turbulent random flow.

Mine go in a circle.

[Bill S]

Ugh. Everytime this conversation starts up, I go back to the real world. Ever been on a reef? Having been on hundreds (we charter sailboats on vacations), the reef is seldom if EVER a "back and forth" wave action. Is there a pulse to it? Sometimes, but its a strong flow/slow flow, NOT back and forth. In any case, the effect of a wave is only felt at 1-2x the wave height. Below that, it's all CURRENT, which is generally constant, and unidirectional.

So, it is an absolute myth that SPS requres/needs/wants "wave action". If you have any doubts, go back and look at the old photos of my tank when it was full of SPS. As Erik noted, mine are all set up to produce a clockwise rotation in the tank (from the top down), with shear in the middle and at the top from the return.

What really drives me nuts is the wave boxes on like a one second cycle. Poor fish, it will wear their tails right off! The period between waves is generally 5-10 seconds.

[SoLiD]

Both of my tangs like to ride the flow directly in front of the wavebox power head. I mean like 4-6 inches in front of it. It looks like they are surfing. Plus I have the photo sensor in place to where it only runs when the halides kick on. It is also great for eliminating dead spots because when it comes on it Always, I mean Always kicks up the crud on the bottom that has collected over night and gets it out to my over flow.

BTW: I have about a 2-3 inch wave on mine.

[SaltyJim]

I have to agree with the corals need for laminar flow. I think that is more important that the constant back and forth, but the laminar flow has to be from multiple directions to avoid undesirable growth patterns. You don't see much SPS in the tidal zones, they tend to be below any wave action. So, that being said, I also have mine in a clockwise fashion, with the rockwork more in the middle to keep the 2 flows (front and back) separate.

The corals will grow into a plane of water to disrupt it for its optimal usage.