Enough water movement?

[redsman]

I have one Maxi-jet 1200 powerhead and a Grech GUP-02 powerhead.The Grech powerhead I couldn't find anything on them online.Anyone know anything about them?How much movement do I want in a 90 gal. Reef tank?The person who had it setup before seemed to have it putting out enough flow.But the left side has a lot of algae,and I think it could be from not having enough movement on that side.I have one head on each side.Should I get another head,move them or what?Is there an amount of gph I should get?

[thegrun]

The general rule of thumb is a total of 15-20 times the DT flow GPH for a fish only tank, 25 times or so for soft corals and 35-40 times for SPS corals. Rock configuration will dictate the number of powerheads/returns needed, but for a 90 gallon tank one on each side will usually do the trick.

[cloak]

Here's a good article.

http://www.advancedaquarist.com/2003/4/beginner

[redsman]

Ok well I just put an extra maxi 1200 in the back.So now I have one on each side with one blowing toward the front.

[doctorgori]

Originally Posted by redsman

I have one Maxi-jet 1200 powerhead and a Grech GUP-02 powerhead.The Grech powerhead I couldn't find anything on them online.Anyone know anything about them?How much movement do I want in a 90 gal. Reef tank?The person who had it setup before seemed to have it putting out enough flow.But the left side has a lot of algae,and I think it could be from not having enough movement on that side.I have one head on each side.Should I get another head,move them or what?Is there an amount of gph I should get?

...might need more info: you didn't say what you are keeping or what your return pump is or if you got wavemakinbg capability, et:

this is usually the type of post where someone says spend $500 on a powerhead or bust (a Tunze or MP40) ...heck I'm surprised it hasn't happened yet... so until we both go down that road (and we WILL eventually) ...
perhaps you could get away with 4ea "Mid-Level" Koralias: 2 per side

Right now 1050's and 750's are on sale at Big Al's for $26 & $36 respectivley, ...

thats what I got running on my 90, although I wish 2 of those were 1400's, but I couldn't figure out how to get more flow w/o blowing sand everywhere ... I'd bet 4X the 1050's would be "safer"

Anyhow, You could theoretically spend $124 and be set ...I would think

[redsman]

I have some coral and fish.My return pump looks like it came from a place like HD for ponds.It's pretty heavy.I don't see a manufacture name on it.The only wave make capabilities I have are with my hands.

[Ron Reefman]

Originally Posted by thegrun

The general rule of thumb is a total of 15-20 times the DT flow GPH for a fish only tank, 25 times or so for soft corals and 35-40 times for SPS corals. Rock configuration will dictate the number of powerheads/returns needed, but for a 90 gallon tank one on each side will usually do the trick.

I'm just curious. Where did you come up with these numbers? In the link that cloak provided it said, "As with any complex subject in this hobby, people are always looking for (and giving) rules of thumb. With regard to water movement in reef aquariums, many authors will advocate at least 10 times the volume of the aquarium per hour. So if you have a 100-gallon reef, you should be moving around 1000 gallons/hour." That's a far cry from 35-40 times per hour. I turn my mixed reef about 25 times per hour and have very complete and random flow. 35-40 times seems a bit excessive. Do you have any support info or is this your informed opinion? Just asking.

[Palting]

AFAIK, most books recommend 6-10X tank volume for a FO or basic reef tank. It's SPS dominated tanks where all hell breaks loose, with recommedations ranging from 20X to 40X tank volume, even 50X. Depending on how you set up your powerheads, 10-20X for a mixed reef and probably 20-30X for an SPS dominated reef should be good enough. I have about 38X in mine. The problem with flow in the tank is the same as the problem with horsepower in a sports car. People think they always need more !.

[sponger0]

I have a Biocube 29 with only 643gph flow and my SPS are doing extremely well. Thats about 22x the water volume

[redsman]

So having two maxi-jet 1200 @295 each and unknown amount on the one.If I'm supposed to get 20-30 times my tank I'm way under than right?

[doctorgori]

Originally Posted by redsman

So having two maxi-jet 1200 @295 each and unknown amount on the one.If I'm supposed to get 20-30 times my tank I'm way under than right?

Man I'm not one to justify gazzillions of bucks on the latest trendy gadgets but I have seen MP40's in action...you'll end up there just like every one else...

in the meantime, you almost gotta upgrade from those mj1200's..I got 2 of the "alleged" newer water movement type and what is that word....oh they are too "laminar" ...fancy talk for the dang things blow in basically a straight line... (and they are now relegated to mixing Instant ocean)
...you say you got a 90G?
I'd think about investing in some Koralias if money is tight and perhaps sweet talks your significant other to give up Xmas for an MP40 or two

2ea 1400's and/or plus maybe 2x 1040's (or 4x 1040's) ....you're gonna need $150 if you catch the current sales

[redsman]

Wow those mp40 are exspensive.It would take more than one Christmas to get one.When I seen the price I nearly fainted.If it is gonna cost that much I will just stir my tank by hand.

[cassidjc]

I know this may sound like a stupid question but I haven't been able to find the answer yet. As mentioned before http://www.advancedaquarist.com/2003/4/beginner says you should use 10x your aquarium volume for flow. I have a 55 gallon so I assume I should use a powerhead with around 550/gph. Should I use just one powerhead or 2? Also if I was to use 2, should I use x2 550/gph or x2 powerheads that equal around 550?

[cloak]

FWIW, I have two Koralia #2's (750 GPH) and a #1 (425 GPH) in my 20 gallon tank right now along with a Rio 2500 as a return pump. That's quite a bit of flow in such a small tank. Some of the LPS corals I have don't seem to mind it right now, (frogspawn, bubble, galaxea) but I think I could probably get away with upgrading.

[Palting]

Originally Posted by redsman

Wow those mp40 are exspensive.It would take more than one Christmas to get one.When I seen the price I nearly fainted.If it is gonna cost that much I will just stir my tank by hand.

LOL!!! I know just how you feel. OTOH, you don't need that expensive nonsense to grow great coral. I just use mutliple Koralia Evos, see my sig, and they cross paths and create excellent varying flow. I have excellent SPS growth, and the K Evos have been running for over a year with no issues. Smart money, as far as I am concerned.

[heckfire]

ok,, this is just funny to me,, i have about 2000 gph in powerheads and another 1500 gph minus head loss, coming out of my fuge,, in a 65 gallon,and i still get massive detritus buildup

[hollister]

Yea 25 times flow good base but placement important. One low and one high on oppisite side trying to creat a strong circuler motion.

I say whene feeding add a little extra and look for low flow or dead flow spots and move or add power head to controll this.

[redsman]

So really were looking for a small hurricane in a glass rectangle.

[doctorgori]

I'd bet if you could some how survey the tanks that had the most problems and those that had the least, my guess is those with the least amount of cyno outbreaks, diatom and hair algae had more flow...

those tanks with caves and lots of space between rocks seem to just look better...
...yeah I got the ole skool cliche' look of a wall-o-rock but I usually make sure my rock isn't leaning against the back glass (I leave 2-3" of space in back)

Basically you gotta have flow across the rock and over the sand bed...no dead zones...

in short if you can't afford those trendy $300-500 buck powerheads get a few Koralias at least...use that MJ1200 and blow across the back of your rock

[Ron Reefman]

Originally Posted by heckfire

ok,, this is just funny to me,, i have about 2000 gph in powerheads and another 1500 gph minus head loss, coming out of my fuge,, in a 65 gallon,and i still get massive detritus buildup

Just having a big number for turnover in your tank doesn't mean you solve flow problems. You can run a much smaller flow and have it delivered to the tank way better and never see algae, cyano or detritus problems. It isn't just about turnover. Why do you think there are so many gagets you can buy that move the flow around? It's also about where you put the flow. And the more you can move it around the better.

[Curious George]

I like 15-20gph*tank volume for a reef or 8-12gph* for a FOWLR

100 gallon reef = 1500-2000gph reef or FOWLR tank=800-1200gph

Anything more than that is not necessary IMHO. For delicate fish, I have gone with less flow and it has worked out well. I was watching a Japanese video of a tank that had a peppermint angel in it. The tank was maticulously set up for success with this rare fish. The one thing I noticed was how calm the water was. I cut back the flow in my FOWLR tank and the fish are very happy, got through a tough time, eat well, the water is clear, and phosphates are low so my live rock stays algae free. True story.

[Palting]

Originally Posted by doctorgori

in short if you can't afford those trendy $300-500 buck powerheads get a few Koralias at least...use that MJ1200 and blow across the back of your rock

It's not about affordability, it's about smart money. Sure, it's cool to be able to set your wavemaker to lagoon mode or tidal mode or, as redsman put it, hurricane mode, but you can have excellent coral growth without it. It is fun and cool, but unnecessary IMO.

And Redsman, it doesn't have to be a hurricane in a glass rectangle. Ron Reefman put it best in his post above, I think, so I'll quote him.

Originally Posted by Ron Reefman

Just having a big number for turnover in your tank doesn't mean you solve flow problems. You can run a much smaller flow and have it delivered to the tank way better and never see algae, cyano or detritus problems. It isn't just about turnover. Why do you think there are so many gagets you can buy that move the flow around? It's also about where you put the flow. And the more you can move it around the better.

[Ron Reefman]

Thanks Palting. Improving flow is why I've raised my rock off the sand on elevated eggcrate. Why I have about 2000gph blowing out of 2 'spraybars' that run on a SCWD and alternate left & right sides of the back glass behind the rock. And I have 2400gph CL using an Ocean Motion 4 and their Revolution heads. Talk about random flow all over the tank! At only a 25x turnover rate, I can take a turkey baster and blow at the LR anytime and almost never get any detritus to blow up. BTW, I do turn off the CL system 4 nights a week and feed corals one of those nights every week or two.

[doctorgori]

Originally Posted by Palting

It's not about affordability, it's about smart money. Sure, it's cool to be able to set your wavemaker to lagoon mode or tidal mode or, as redsman put it, hurricane mode, but you can have excellent coral growth without it. It is fun and cool, but unnecessary IMO.

And Redsman, it doesn't have to be a hurricane in a glass rectangle. Ron Reefman put it best in his post above, I think, so I'll quote him.

YUP! I couldn't agree more (I myself take few dozen shots at those pricey powerheads just here on RC), but we all do love our tech toys don't we!!!

...just talking here....

...but to the point of those MJ1200's...I recently bought 2ea along with 2 Korillas from Big Als or somewhere...things were on sale for just $19..... In short I thought they sucked in thier new "modified role" posing as circulation powerheads... IMHO the flow just isn't wide enought (I think the $1000 word is "laminar")

I can't see the $300 xtra for a MJ40 vs a Korallia (no matter what someone argues a MJ40 it does not perform the same task 10X better!) but I think the $20 xtra for a Korallia vs. a MJ1200 is definetly there