40g Hex Tank Flow Question

[superkat]

Well since the search didn't bring anything up....

I have a 40g Hex that I just set up (again, thank you Will, Liam loves it.) and I have some questions regarding flow and placement of powerheads. I would like to be able to have some LPS in there for him...mushrooms.

Here was my idea...what i started anyway...i have two nano k's and one small pump on the bottom center shooting UP with the rock stack around it...the flow shoots straight up through the rock. I'm still getting a vortex sort of flow pattern, even positioning the nano's in a bunch of different places.

So...ideas? Suggestions? Thanks in advance.

 

[RyanEG]

With a near cylindrical tank I think your always going to struggle with a cyclical flow pattern. How do you have the tank set up? Any overflow? Where's the rock stack? Centered or back wall

 

[superkat]

it's not drilled...although i think that's something i want to do...just afraid of that...and not sure where to start except glass holes...which gets huge kudos here. Right now i've got a CPR bac pac and a HOB filter. The rock stack is in the center. Nothing touches the glass.

 

[RyanEG]

What's wrong with the cyclical flow? You could always get a couple maxis and set them up with a wavemake type timer just to randomize it. I think someone had a red sea one for sale recently.

 

[superkat]

that might work...just as a test...i put some of my anthellia in there to see what the flow pattern was...and every way i tried, it never really got that back and forth wave. So i'm thinking maybe a waver might be good from what you suggested. I don't remember who it was that had four powerheads with one dedicated to random flow...even off sometimes. Maybe Steve. I thought with putting flow directing upwards through the rock, that might help...

 

[der_wille_zur_macht]

Don't put too much stock in random flow or "waving" of corals - IMHO it's more a benefit to us human observers than a requirement for coral health. IMHO since you have a tank that's easy to create gyre flow in, you should take advantage - it can be a cool way to get a lot of inertia built up with a small amount of effort (i.e. few pumps).

 

[superkat]

oh shoot....NEVER thought of that at all. Holy Cow. Because right now...it's like what kids do in a small round pool...walk around and around and then ride the flow. Now...next question...will that drive fish crazy?

 

[der_wille_zur_macht]

It will probably have less impact on their psyche than the fact that they are trapped in a tiny glass box. :lol:

Some people who deliberately attempt gyre flow include two "sets" of powerheads/pumps, such that one set creates flow in one direction, and the other creates flow in the other direction. Then you can put them on timers with approximate 6 hour switching frequencies - this will roughly imitate the natural changes in the overall direction of flow as the tide changes directions on a real reef.

 

[mynock11]

What i did Kat was pointed the pump at one of the panes of glass and let it ride never had any issues with the flow in that tank i think do to it being the shape it is helps with the flow. my only suggestion is either put 1 near the bottom and point it slightly up(Wich is what i did) so it kinda takes the water from down below and cirulates it or put 2 in it one above the other.i had a remora HOB skimmer on it and an aqua clear 30 did fine.I believe it is a 27g correct me if im worng but the measurments were the same as the ones i got off a tank at a store and it was a 27g.

 

[Grenade Glass]

My first tank was hex shaped. ran into the same problem, ended up using 2 maxijets on a wave maker, seemed to do the trick. I did run into someone on reef central that created a PVC return from the sump. The piping went around the top of the tank, right below the edge of the aquarium, and had many small holes drilled into it. This allowed water to return to the tank in many directions, not sure where your going with this tank but if its going to be SPS dominated it might be a good idea to look into.

 

[superkat]

I have very little luck with SPS. The only tank that really has supported it (even in the midst of a series of catastrophes) has been the 90g. Since this is my son's tank, i plan on doing simple LPS and shrooms, palys. He's five, and already loves to stack rock and knows all the names of the corals in all my tanks. So this has been the mommy/son tank...i'm letting him (helping him) arrange the LR and pick out what he wants for coral. Fragging from the 120g. Love that I can do this! Frag back into another tank. Will, i lost count, but i think it took more than 6 buckets of saltwater to fill the hex. Since someone else confirmed that it was a 27g, i'm tending to think that I am wrong. Grenade, i LOVE that idea. Right now i just have the HOB and the CPR bak pak...but want to figure out a way to sump from underneath...gonna need to be creative since the stand is tall and won't support a sump that is shaped lengthwise.

Currently I have 3 powerheads in there. The two nano k's are pointed so that the flow meets at the front of the tank and seems to circulate backwards nicely, but still end up getting that circular flow. So I placed another powerhead at the bottom and it is shooting directly up through the rock stack...it diffused that circular motion slightly...but it does tend to end up "whirlpool-ish" from time to time. The flow with the 3 is EXCELLENT...was just concerned that the steady circular motion would be bad...

you guys are great btw, thank you SO MUCH for all the input.

 

[johno4]

Some people who deliberately attempt gyre flow include two "sets" of powerheads/pumps, such that one set creates flow in one direction, and the other creates flow in the other direction. Then you can put them on timers with approximate 6 hour switching frequencies - this will roughly imitate the natural changes in the overall direction of flow as the tide changes directions on a real reef.

This seems like a really good idea

 

[superkat]

i like this idea as well...bought two timers today at Wallies...heh heh. thanks DWZM.