Flow questions for Acropora in mixed reef.

[camaroguy]

I currently have a 125 gallon mixed reef. It is the standard 72"x18"x22". I have rockwork that stacks to about 50% up on the left, about 80% up on the right, and about 40% up in the center. The rock runs mostly toward the back and center. This rockwork runs basically the entire length of the aquarium.

I have some LPS in the sand and some of the lower rock work, and currently have a few SPS on the upper right (purple stylophora and pink birdsnest. These seem to be heathy and I have had them for over a year.

On the upper left is a giant RBTA and a leather coral (it came on the rock), they I have had both of them for about 2.5 years.

I would like to start trying some acropora on the left and possibly the right. I want to dial in the best flow characteristics though.

Currently I have two Tunze 6095s that are pointed at eachother from opposite sides of the aquarium. They are positioned above the rockwork and are on a program as follows:
1. Left at 30%, Right ramping between 30% and 80%.
2. Every 6 hours, reverse roles

I am considering getting 2 more of these pumps, but am not sure how to position them. I would also like some advice on the programs or if it is better to just leave the pumps on a constant rate (simpler is better)?

Thanks

 

[camaroguy]

Maybe I could simplify the question a little.

Are more powerheads with constant flow better than complex programmed ramping logic?

Or is it better yet to have more powerheads with all of them keeping the complex ramping logic?

Or maybe a mixture of the two?

 

[MondoBongo]

i'm running two mp40s in my reef. it sounds like we have a roughly similar rock strucutre and tank footprint (mine is a 150 long, or 160 depending on who you're asking. 72"x18"x29")

i tend to think that random flow is better than laminar flow, although i have no direct evidence to support that.

flow can be a tricky thing, and before i go adjusting mine, i usually just try things first. typically i judge the effectiveness of the flow of a particular area by polyp motion. i like to see the polyps on my SPS gently waving in the flow, with the occasional harder flap, or gentle slowing.

what can be real telling is the growth patterns of the corals. that's a lagging indicator, and i'm still trying to get more of a sense of how to anticipate it, but in certain spots corals will grow bushy little colonies, in others they tend to bend out of the way, or in to the flow.

so all this to say that i would probably get a frag or two and just give it a try placing them around. see how they do. flow for me has always been more art than science.

it's also probably easier to add new powerheads than to adjust the existing ones. maybe this is just me, but it seems that whenever i adjust a powerhead, i had a real hard time getting it back in place if i do not like the change.

 

[markalot]

I also have a 150 and use two MP40's on reef crest either side and a couple of RW15's in wave mode attached to the back wall aimed toward the center. I was able to keep a gold torch, duncans, and trumpets happy near the bottom of the tank for nearly a year with this setup.

 

[camaroguy]

Interesting about moving the powerheads. I have to remove my powerheads every few months to clean them, its almost impossible to get them back in the exact same position again.

 

[MondoBongo]

Interesting about moving the powerheads. I have to remove my powerheads every few months to clean them, its almost impossible to get them back in the exact same position again.

at least i'm not the only ones. it's a little easier with the mp40s because there is no up/down/left/right adjustment on the wet sides of them. so as long as i don't change the X or Y axis it stays relatively the same, but when i had the Koralias that could be oriented X and Y axis, and what amounted to roll, pitch, and yaw, i could never get them back where i had them.

 

[JojoAZ]

I had almost the same placement as you when I started adding acropora, I run an RW-8 on both sides at full power and everything is thriving. Before I just had a constant flow across the top and it had adverse effects. I find that as long as the flow is changing the corals can take whatever you throw at them. I have a huge RBTA up at the top as well, just give him space or he will kill whatever acros are around. As for that leather you might as well pull that thing now. I had one that was a hitchhiker kill half of a beautiful tenius. I believe they release toxins that are detrimental to SPS.