In - Tank Circulation Rates?

[AJ_77]

Seeing as we're snowbound, let me ask you:

If I have ~630 gph from the return pump, spewing into the 90g tank from 3 outlets, then how many powerheads (and at what flow rate) should I be using, to get a moderate flow happening?

Keep in mind I'm not big on the "windblown" look, and don't like a lot of visible gear cluttering up the display tank. And a closed loop is out of the question for now.

Thanks, you know the kinds of beginners corals I'll soon have,

Alan

[ 06 May 2002, 13:12: Message edited by: AJ_77 ]

[Canadian Man]

Hey Alan, how you doing?
I would add 2 Mj 1200's in the corners of your tank and that should be perfect for the corals we/I am supplying for ya!
Thats aprox what i figure/hope i will get from the return pump from the basement to my tank and i will add 2 mj1200's in the corners @ 295 gph, to replace my rio's @ 700 gph.
hope this helps.
looking foreward to tues evening!

[Delphinus]

I know you what you mean about the visible gear. Unfortunately it's a good and economical way to get customized flow. So it's a trade-off I guess...

Of course, it all depends on what you like, but I've found you can't have enough flow. Kind of like lighting. I always want to "pump up the volume" just that little bit more. Of course, you don't want water velocity to the point that your sand never settles. Fortunately, water velocity and water flow aren't exactly the same thing.

The problem with increasing flow via your sump return is that more water ends up going through your sump and overflow. This can get noisy and lead to microbubbles, and etc. You want some good flow from your sump return (IMO) but not so much to overwhelm your system.

I'd start off with two powerheads (i.e., Maxijet 1200) at either side of the tank, laterally opposed (ie., pointed towards each other). The turbulence you get where the waters meet will good and randomized. Then see how you like that after a few weeks. If you want more, then jump off that bridge at that time. Maybe some bigger powerheads or some other (strategically hidden) powerheads, or, maybe, nothing more at all because you like it just fine that way.

(My bet is on that between your sump return and two powerheads, you might be happy with that.)

cheers

[AJ_77]

Hi Jon, doing great thanks. Looking forward to tomorrow evening also! I hope they clear the streets for you guys - does Tony have a Hummer maybe? ;) (Hi Tony - sorry you had to go in today. :D And thanks for a quick and thorough reply!)

I'm wondering where the PH's should go depth-wise in the tank, seeing as surface flow seems to be desirable. The critters needs a calmer place near the sand, no?

I bought a Hagen 802 'cause Danny has them on sale - taking it back tomorrow. Silly thing says not to submerse it. And it vibrates - piece of crap. Going with the MJ - but the 1200 sucks way more power than the 900. Still good flow?

Cheers, comrades

Alan

[ 06 May 2002, 22:06: Message edited by: AJ_77 ]

[Canadian Man]

Well I am off tommorow but havent organized any rides.Anyway, to stay on topic ;)
I would put the ph's at the surface if you are adding 2. if your returns are near the surface they may provide enough agitation so you could put the mj's a little down but i wouldnt put too much emphisis on it just put them where they will mix the current up the most.

[Delphinus]

I keep mine near the top too. (Pity that the earliest meeting I could host is July, because I really want to point at things in my tank as I make these explanations. Oh well, do you mind waiting until July? J/K! :D )

But as Jon said, it's not a real biggie. Whatever you like best. You do want some surface agitation one way or the other, whether it comes from the sump return or PH's or a spray bar ... doesn't really matter.

Um. What else was I gonna say? Oh yeah. 802's. A decent workhorse PH, but yeah RATTLE RATTLE RATTLE. I use one to run my refugium off my 50 and another to run my spray bar for my ritt (serviced from the sump so it acts as a secondary sump return as well). Oh, it might be OK to mix up saltwater in a pinch. But other than that ... I'd never consider one as a PH in my main display tank. Not too nice to hear that constant jackhammering.

You'll be hard pressed to find a nicer powerhead than the MaxiJet's (at a comparable price that is).

(And hey Jon, if ya wanna car pool I'd be game, almost silly not to since we live to close to each other ... let me know.)

cheers guys

[Canadian Man]

Works for me tony!
I was planning to be there a little early like 7:00 to facilitate getting the sand from alan.
i would happy to drive as long as you dont mind riding in my city block(aka 85 crown vic)
you going to be home @ 6:00pm? if so i will pick you up then.

[Delphinus]

Well, I don't mind to drive either. I don't have a city block though [img]smile.gif[/img]

Now, the only thing is, I have to make some cuttings and such before going, otherwise I'm coming to the meeting empty-handed. So 6 might be a bit rushed for me. Can we play it by ear tomorrow maybe?

[Canadian Man]

No problem mon!
let me know. like i said i am off tommorow and will be around all day. will be checking my mail and message board all day.