Another water movement question.

[Keith A.]

I have a 75 gal reef tank with some stonies, LPS, leathers, button polyps, mushrooms, etc. I have a 1200 gph return pump in my sump. After all of the tubing back up to the tank and through a SCWD, I'm getting roughly 800-900 gph. The two returns for the sump pump are in the top back corners of the tank. They are pointed down at the opposite corners in the front of the tank so they essentially make an "X" pattern of water flow in the tank. I also have a small power head, center, on the top of the back of the tank pointed down at the bottom of the front of the tank. This powerhead is about 120 gph so in total I'm getting 900-1000 gph or so.
I'm thinking about getting 1-2 powerheads in place of the small powerhead in the top center of the back of the tank and I'm not sure what to get. I would like the total GPH to be between 1800-2000 GPH (hopefully that's not too much). I'm not sure if I want to get two small koralia (size 1 or 2), one bigger koralia (size 3), or one or two regular powerhead(s). If I get one unit, it would probably be pointed in the same direction as the one I have in there now. If I get two, I would put them side by side in the same spot and point them to the bottom corners in the front of the tank, essentially going from a big 1 "X" pattern to 2 smaller "X" patterns in the tank(one on each half of the tank). Hopefully this makes sense. Which do you think would be better? Any feedback would be appreciated.

Thanks,
Keith

 

[HN1]

I'd say 2 patterns are better, but it will really depend on your rockwork. Tinker with them overtime and watch your corals. They'll let you know what they like.

 

[bavass]

I love my two Hydor Koralia its a lot of soft water movment

 

[abrahamavelar]

i have a 75 gal and i use 2 koralia number 3 and i get really good flow

 

[thincat]

How much money are you willing to spend? The two Koralia #2's are great for a tank your size, but it depends on if you want to use a wavemaker in the future. You can mod the koralias for a wavemaker but Maxijets are better for that purpose.

 

[ccCapt]

I question the rate of your return pump. How many overflows do you have and what are they rated for? If it's a ReefReady predrilled tank, it comes with 1 overflow capable of handling aprox 600 gph.

When I had my 75 running, I used 2 K-3's and a 600 gph RIO powerhead. The K-3's where in the back corner pointing towards the front center and the Rio was in the back center pointing towards the front.

 

[Jaybird]

I've got a 90G with two Koralia 4s and a maxijet 1200. The return pump is probably doing about 600-800GPH and each Koralia is positioned on the side of the tank (one close to the front glass and the other close to the back) and pointed slightly up. The maxijet is on a wavemaker bar but I'll likely be replacing it soon for a koralia nano. As for flow, I have candycane that is about seven inches from the front, and a bit off to the side, of the one koralia4 and it seems to be doing very well. The only thing in the tank that doesn't seem to be doing so well is the frogspawn. It's just not opening up much.

 

[thincat]

Is the PH really blowing the frogspawn out the window? They seem to like a fairly strong current, but not overly strong.

 

[Jaybird]

Not any more than enough to gently wave the tentacles. I've got a finger leather that loves it almost in front of the koralia4. The frogspawn just gets a gentle flow and lots of light

 

[Keith A.]

Here is a pic of my 75 gal tank so you can see the rockwork. I have a SCWD on tha back of it so I wasn't really thinking of getting a wave maker. The trickle filter is designed for a 150 gal tank. I was originally thinking about getting a bigger return pump in the sump. However, the pump that I would need to get the gph I want would be physically too big for the sump part of the filter. So I decided to go with the powerheads instead. I have the two returns in the top back corner for the return pump from the sump and a powerhead on the back of the tank in the middle top. I was thinking about replacing the powerhead for one or two powerheads or one or two koralias. From what I understand, the koralias have a bigger exit nozzle than a powerhead and moves water more like a wall where as a powerhead, with the smaller exit nozzle, would move the water in more of a narrow stream. Is that correct? If so, Would a stream flow be better or more of a bigger wall flow? Would the powerhead move the water a further distance in the tank than a koralia?

Thanks for the feedback so far.

Keith

 

[thincat]

You're correct on the difference between the flow of the Koralia and the standard PH. The K has a better footprint in my opinion. My tank had a total of 5 PH's and I replaced them with one MP-10 and a K-2. Less heat in the tank plus more water flow.

 

[Jaybird]

From the picture, are those two maxijets in the left and right corners? Those should be great spots for a 75g tank

 

[Keith A.]

Jaybird,
No. They are the returns for the pump in the sump. The one in the middle is a aqua clear powerhead. I stopped by my LFS over lunch today and dipped my hand in a tank that had a koralia 4 I believe. I couldn't feel the water movement after about 10-12 inches from the end of the pump. Is this typical or did they just have a bad pump?

 

[thincat]

That's about it, but they stir up allot more water then a Maxi-jet of the same size. One is a jet of water through a small openning and the other is a Prop. that moves lots and lots of water.

 

[abrahamavelar]

+1 also i might be wrong but i have mine on bothsides of the tank, and i have them on diferent corner and i still get good flow my tank is 75 gal and i have 2 koralia 3 and i think thats more than enough water movement you dont want it to be strong enough to push ur fish around or move rocks JMO

 

[Jaybird]

You should feel water movement a couple of inches in front of a koralia4. Mine give a nice gentle movement on the opposite side of the tank from it. I've got a finger leather about eight inches, and slightly below, the rear koralia4 and it jiggles like jello. It loves it and spends all it's time with the polyps extended.

the 4s push about 1200gph, so you should feel it

 

[abrahamavelar]

yup and i think the 3 do about 800