Flow Advice Please

[Drez]

Flow

It’s always been a tricky thing to me. I see people with nanos and they’re pumping out 40x turn over but it doesn’t make sense to me. I have a MJ1200 (300gph) and I feel like it’s too strong already, then the nanostreams are twice that (albeit diffuse); I wonder if they will fix or make problems.

Flow is an especially important topic right now to me as I’m fighting algae growth. It seems like a delicate balance, not enough flow algae grows on my corals. Too much and the corals don’t like it.

I already reduced light to 8hrs, raised the lamp, feed bidaily and have some Phosguard in the tank. So flow might be my only way to go. I’d also like to have a flow I’m happy with a on a permanent level so that I’m not stressing the tank with changes.


This is the flow dynamic I’m attempting to incorporate into my tank. It’s based on this article http://www.advancedaquarist.com/2007/1/aafeature
and the pumps I have, but I’m open to ideas.

Please corrections, advice or encouragement are all welcome.

At present this is the set up. The big line at the back is the flow of the MJ1200 (aprox 300gph) brushing the back wall and following it to the skimmer box and first rock where some is diffused up and/or across denoted by the arrows. More continues to the back wall and follows around, and then the rest circulates in a circle back to the source. It’s rearranged the sand a bunch but its not stressing anything as is so I’m fairly happy with that. On the opposite wall a MJ400 gives off a weak flow (aprox 100gph w/o attachment) with the hydro flo attachment that is giving a light wave action. The second MJ400 (again aprox 100gph stock) is modded and so it puts out a little extra flow and is more diffused. It’s at the blue star but I plan on putting it at the blue B providing it doesn't cause the corals in front too much stress. I may put it high for this reason. Let me know what you think.

http://i138.photobucket.com/albums/q267/aseelisc/Flow.jpg

http://i138.photobucket.com/albums/q267/aseelisc/flow_2_above.jpg

As always thanks for looking!

[supahtim]

chop off the nozzles of the Maxi Jets to create a more random flow pattern.

the problem i think you are having is that your flow is all directed in a tight pattern. you want a more random flow. the hydor attachment is a good start.

and try to keep the water level topped off. with a small tank like yours, the more you let evaporate, the higher the salinity levels go at a faster rate.

Tim

[icyuod2]

hey drez personally i'd change the placement of the powerheads. put them on the back wall facing the front glass (i'd angle them towards each other -it will make the water more turbulant.)

the flow will deflect off the front glass and role down and towards the back of the aquarium.

have you given thought to a wave maker? theres a wavemaster controler in the classifieds for $125. ya plug your powerheads into it and it will vary from gentle to strong current, switching back and forth between the 2 powerheads.

[Drez]

The chopping off is basically the mod thats done to the MJ400 except the intake is also opened up (idea thanks to Travis at Nonoreefs). I did the same thing to the 1200 but its was tossing up the sand below it in a brutal sandstorm fashion. I switched an un modded base back on and let it cross the tank in hopes that the length of the tank would do the job for me. It did realativly well till it gets to a rock narrow where it sucks some sand with it again. Maybe I'll try again and move it up higher, it'll probably help that the tank level is full again.


Your defs right about top off though, I might have to establish some auto top off in the future. A good eye as the pic is a record low, I was out of RO/DI and my RO/DI isn't up and running yet. Since I'm battling algae already I didn't want to add tap.

[Drez]

Icyuod

Won't it be a problem that the 2 powerheads are of different GPH, wont the 1200 negate the 400 and just push in the direction its facing? Do you think it will matter if the all the turbulence is right in front, thats where the majority of my corals are. I might be able to shift the rocks to the back although I wont be able to scrape the glass then though.

What about pointing the from side front to back so the rocks act as a baffle? Unorthodox and a little ugly but could work.