flow advice ???

[Ronan021]

hello

i am trying to work out the best flow for my tank
using the current equip that i have to work with... i had way to little flow for the first 3-5 mos tank was set up resulting in detritus build up in the DSB = now dealing w/ high phosphates in the tank (getting phosban reactor)



so here is what i have:

125 mixed reef
200# LR (spread out into 2 islands split down center tank)
custom glass tank, not standard 125 (5 foot long)
corner overflow

mag 9.5 return from sump
split off w/ x2 locline each w/ eductors to incr return flow
5 foot return from sump to main display

odyssea 1200 L/hr powerhead
(approx 700 gal/hour)
has locline attached so flow can be better directed
pretty strong (monstrosity of a) powerhead that creates a lot of flow

2 rio 600
which i basically just use for surface agitation in main display



i have tried different configurations of flow
in the tank... the odyssea is pretty strong and placed up high on one end (opposite overflow) it will blow all the way to the other side (lengthwise) and around creating a gyre type effect but in the process creates way to much flow for the corals located in that end of the tank (star polyps, hammer(s)/frogspawn, mushrooms, XENIA - sitting on the end w/ the overflow ).

this actually seems like the best 'flow pattern' to use...
blowing towards the overflow but again it doesnt work w/ what corals i have on that end of the tank and i would have to redo all the aquascaping in order to change this around... and of course this is the 'area' of aquascaping that has the 'best' display in the whole tank... to move it around would be taking down our most favorite part of the display!

most recently
i have taken the return lines and aimed them at the odyssea to have them blowing towards each other(meeting up high at the center of tank) but its like they cancel each other out... ending up w/ the corals sitting still in the tank w/ no movement hardly at all...


i have read different ideas on directing flow
gyre effect... or pointing all pumps at the same point in the tank (perhaps at the front center)...

what do others do around the back of their tanks say behind the liverock... does anyone put powerheads down in there to incr flow in those areas to cancel out these dead spots (where detritus is accumulating)???

any recoms would be appreciated!

thank you and regards!

[Ronan021]

that was actually 2700 L/hr = 700 gal/hour on that odyssea powerhead

[Fish Filet]

Too many powerheads, in my humble opinion, will make a mess of things anyway. Perhaps a device such as OM or SCWD may be in order on the return lines and the current power heads replaced with a couple of Tunze streams. Just something to look into.

HTHs

[Ronan021]

<a href=showthread.php?s=&postid=10647283#post10647283 target=_blank>Originally posted</a> by Fish Filet
Too many powerheads, in my humble opinion, will make a mess of things anyway. Perhaps a device such as OM or SCWD may be in order on the return lines and the current power heads replaced with a couple of Tunze streams. Just something to look into.

HTHs


FishFilet
thanks for the reply!

the only p/h contributing any significant water flow in the tank is the odyssea... the 2 lil rio 600 are not being used in any signif capacity other then being used for surface agitation which is more or less minor in this application

i am thinking i might move the 2 rio 600
using them to direct water flow down and around the back of the tank... behind the live rock etc...

perhaps down the road
i will purchase some other pumps such as the tunze streams that you mention (although w/ the exception of being an eye sore the odyssea 2700 does move a lot of water!)... but for right now i would like to work w/ the equip that i have...

[aninjaatemyshoe]

First, get rid of the Teed off loclines on the returns. You're not going to get the kind of pressure you need out of the Mag 9.5 to get good flow from the eductors. Also, what size plumbing do you have from the Mag pump? You'll want at least 1.25" diameter plumbing for the return. This will greatly increase the flow rate if you were using 3/4" or even 1".

[Ronan021]

i have already purchased a SCWD
but i havent figured out how i want to use it if at all...

[Ronan021]

<a href=showthread.php?s=&postid=10647368#post10647368 target=_blank>Originally posted</a> by aninjaatemyshoe
First, get rid of the Teed off loclines on the returns. You're not going to get the kind of pressure you need out of the Mag 9.5 to get good flow from the eductors. Also, what size plumbing do you have from the Mag pump? You'll want at least 1.25" diameter plumbing for the return. This will greatly increase the flow rate if you were using 3/4" or even 1".



aninjaatemyshoe
i thought about reducing the return back down to one locline/eductor but i liked having control over the flow pattern using 2... and i would describe the flow coming out (using the eductors) as 'moderate'...

reducing it down to one is definitely something to consider
perhaps being the best place to start...

but then what might you recom as far as aiming the flow pattern?
the return comes from the corner overflow box... would it be best to aim it diagonally across to the other end of the tank or out across to the center glass???

return plumbing = 3/4"
approx 5 foot return sump to display
3/4" locline reduced at end to 1/2" to eductor

[Ronan021]

<a href=showthread.php?s=&postid=10647368#post10647368 target=_blank>Originally posted</a> by aninjaatemyshoe
Also, what size plumbing do you have from the Mag pump? You'll want at least 1.25" diameter plumbing for the return. This will greatly increase the flow rate if you were using 3/4" or even 1".


the bulkhead is 3/4"
would you recom to use 1.25 hose from return pump then 3/4 reducer to bulkhead... then 1/25 again coming out of the bh??...

sorry if that sounded really stupid
but i am not that familiar w/ plumbing a fish tank using bulkheads etc... almost seems like easiest/perhaps best thing would be to cap off return bh (in the overflow) then run 1.25" all way from return pump up back of aquarium to return line in the tank (iow totally bypassing the b/h completely)