circulation issues

[Luca Brazi]

Got a hair algae problem emerging and just want to make sure that my
circulation is adequate before I begin addressing other issues. In a
29gal. with a Mag3 below in the stand driving a SCWD (est. 200gph flow
alternating from each corner pointing toward the center and slightly
down) plus a aquaclear 301 powerhead in the center aimed forward (est.
175 gph) with an aquaclear 150 powerfilter (no media except occasional
bag of purigen) providing surface agitation. Is this, in general,
average circulation, too much (highly doubtful), or too little? Three
small fish, some softies, and assorted snails, hermits, and a
featherduster are the bioload.

For those with SCWD experience, would moving my Mag3 a foot or two
closer to the highest point of the return tubes produce sufficiently
more current to be worth the effort? I can run the numbers based on
manufacturers specs but the 20% penalty for using a SCWD seems too
optimistic if I had to give a quick & dirty estimate from experience.

[Marc Levenson]

Hi Luca,

Since I have a 29g with a SCWD currently, I must answer your question! :)

I have a Mag 5 five feet below my tank's top edge, pushing water up from my
sump/refugium. I estimate the return is 300gph. I also have a Mag 5 sitting
behind the tank with a SCWD moving another 312gph (based on timing and output),
plus an Aqua C Remora with a MaxiJet1200, and another Maxijet1200 inside the
tank.

With all that, I don't feel I have too much current. I've even thought about
pulling the Mag 5 off the SCWD and inserting a Mag 7 to increase the flow.
<grin>

Lifting your pump up higher will decrease the additional head pressure.

Green Hair Algae comes from high nitrates, high phosphates, old light bulbs
whose light spectrum has shifted, and underpowered skimmers.
http://www.melevsreef.com/gha.html

Marc


Luca Brazi wrote:

> Got a hair algae problem emerging and just want to make sure that my
> circulation is adequate before I begin addressing other issues. In a
> 29gal. with a Mag3 below in the stand driving a SCWD (est. 200gph flow
> alternating from each corner pointing toward the center and slightly
> down) plus a aquaclear 301 powerhead in the center aimed forward (est.
> 175 gph) with an aquaclear 150 powerfilter (no media except occasional
> bag of purigen) providing surface agitation. Is this, in general,
> average circulation, too much (highly doubtful), or too little? Three
> small fish, some softies, and assorted snails, hermits, and a
> featherduster are the bioload.
>
> For those with SCWD experience, would moving my Mag3 a foot or two
> closer to the highest point of the return tubes produce sufficiently
> more current to be worth the effort? I can run the numbers based on
> manufacturers specs but the 20% penalty for using a SCWD seems too
> optimistic if I had to give a quick & dirty estimate from experience.

--
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Business Page: http://www.sparklingfloorservice.com
Marine Hobbyist: http://www.melevsreef.com

[Dragon Slayer]

circulation is not going to reduce hair algae by any means and may actually
help it spread.

I have a mag 12 running closed loop which is estimated after plumbing to
have approximately 1100 gph of water flow at the return and I have a hair
algae patch that grows in the spot where the return from the pump enters the
tank. it grows in a "V" pattern in the same direction as the return blows.

IME I have always noticed hair algae preferring places of high flow, I guess
it provides it with more nutrition by passing more water over it during a
day.

I would have to agree with Marc in that:

"Green Hair Algae comes from high nitrates, high phosphates, old
light bulbs
whose light spectrum has shifted, and underpowered skimmers. "


kc

[richard reynolds]

> circulation is not going to reduce hair algae by any means and may actually
> help it spread.
>
> I have a mag 12 running closed loop which is estimated after plumbing to
> have approximately 1100 gph of water flow at the return and I have a hair
> algae patch that grows in the spot where the return from the pump enters the
> tank. it grows in a "V" pattern in the same direction as the return blows.
>
> IME I have always noticed hair algae preferring places of high flow, I guess
> it provides it with more nutrition by passing more water over it during a
> day.
> kc

interesting never gave it a thought, only patch i still have is on my FO, and its directly
in the flow from the return from the sump, it isnt big, and i just leave it, ocasionally
the tangs will consume parts of it, but its only about 4" long by 2" wide. the width of
the return :)


--
richard reynolds