Balancing flow with fish and corals

[Lavey29]

Greetings everyone, I am new to the hobby and seeking some input. I have a Red Sea XL300 (65g DT and 15g sump). It was fast cycled and has been running a month now. I have a Vectra M2 return pump at 40% for flow via Y pipe nozzle and an MP40 side mounted. There is a lot of rock scape with good caves and flow shield areas. I recently added 2 clownfish to the tank about 1.5 to 2" long. There is no coral in the tank yet. I originally had the MP40 on Reefcrest mode at 30% and over the past week it seemed like the clownfish were somewhat struggling with the current. They surfaced to get food fine but were not exploring the tank and just stayed mainly in a back corner of low flow. I have now changed the setting to Lagoon mode at 30% and notice that the fish seem to be moving around the tank more and swimming more at ease. Obviously Lagoon mode is less harsh then Reefcrest so I have a few questions:

Were the fish struggling initially because they were probably captive bred and not used to the flow? Would they eventually adapt or would they eventually die of fatigue and stress? I hope to begin adding corals which would probably consist of soft and LPS type corals which typically do ok with lower to moderate flow levels from what I have learned but what if the corals require something like Reefcrest to flourish better? I know some fish do better in high flow also then others but for a general reef community tank how do you balance the needs of the fish with the needs of the corals? Is it better to try and get the fish to adapt or get the corals to adapt to a specific flow rate?

Thanks in advance for any helpful suggestions.

 

[Biokabe]

Generally speaking, corals are much more concerned with flow than fish are. Some fish are sensitive to flow - seahorses and pipefish, for example - but generally speaking they're all more than capable of going with the flow and adapting to it.

Clownfish in general tend to be more "sedentary" as far as fish go - in the wild and in our tanks, they like to claim a particular spot as their own and they don't stray too far from it. This is particularly true if they start hosting an anemone.

In terms of balancing flow requirements in a mixed reef tank... well, it's complicated. I can tell you what I do in my tank, but everyone has different ideas, and there is more than one way to run a reef. I have three programmable powerheads (two Apex WAV pumps, one Maxspect Gyre pump), set up so that they're blowing in different directions - my two WAV pumps run from the back of the tank to the front of the tank, with the Gyre pushing water across the length of the tank. I have all of the powerheads higher up in the tank, so that most of the direct flow is going across the top of my rocks, where I keep my high-flow corals. For most of my low-flow corals, the return line from my sump points down towards the middle and bottom of the tank, so the flow spreads out along the bottom. Lots of indirect flow in the lower part of my tank, but most of the direct flow is blocked by the rocks higher up in the tank.

 

[Lavey29]

Generally speaking, corals are much more concerned with flow than fish are. Some fish are sensitive to flow - seahorses and pipefish, for example - but generally speaking they're all more than capable of going with the flow and adapting to it.

Clownfish in general tend to be more "sedentary" as far as fish go - in the wild and in our tanks, they like to claim a particular spot as their own and they don't stray too far from it. This is particularly true if they start hosting an anemone.

In terms of balancing flow requirements in a mixed reef tank... well, it's complicated. I can tell you what I do in my tank, but everyone has different ideas, and there is more than one way to run a reef. I have three programmable powerheads (two Apex WAV pumps, one Maxspect Gyre pump), set up so that they're blowing in different directions - my two WAV pumps run from the back of the tank to the front of the tank, with the Gyre pushing water across the length of the tank. I have all of the powerheads higher up in the tank, so that most of the direct flow is going across the top of my rocks, where I keep my high-flow corals. For most of my low-flow corals, the return line from my sump points down towards the middle and bottom of the tank, so the flow spreads out along the bottom. Lots of indirect flow in the lower part of my tank, but most of the direct flow is blocked by the rocks higher up in the tank.

So as I begin to add corals focus my flow attention more on them then the fish in the tank? I know I have nothing to compare yet because it's only rocks and sand along with 2 fish in the tank but there is a very noticeable behavior change in their activity swimming while in lagoon mode versus reefcrest mode. They just seem much more happy and comfortable with the lower flow but I wonder what will happen if the upcoming first corals prefer more flow? You think the fish will adjust accordingly and I'm sure you have much more experience then I do.

Thanks a lot for the info.

 

[saltyhog]

I suspect the change in behavior is related to the length of time in the tank and not the flow. What you describe is pretty standard behavior for newly introduced clowns for a while. Suspect the timing was coincidental.

 

[Lavey29]

I suspect the change in behavior is related to the length of time in the tank and not the flow. What you describe is pretty standard behavior for newly introduced clowns for a while. Suspect the timing was coincidental.

Yes, I agree after researching clown fish behavior so I tested the waters so to speak. I switched back to reefcrest 30% for an hour and the fish huddled in a corner behind the rocks. Then I set lagoon mode at 30% and the fish are free swimming and exploring the whole tank. Perhaps having multiple flow programs throughout the day may be best as we all know the tide and ocean flow changes throughout the day.

 

[Biokabe]

So as I begin to add corals focus my flow attention more on them then the fish in the tank? I know I have nothing to compare yet because it's only rocks and sand along with 2 fish in the tank but there is a very noticeable behavior change in their activity swimming while in lagoon mode versus reefcrest mode. They just seem much more happy and comfortable with the lower flow but I wonder what will happen if the upcoming first corals prefer more flow? You think the fish will adjust accordingly and I'm sure you have much more experience then I do.

Thanks a lot for the info.

Basically, yes. Fish can move and find spots in the tank where they're happy with conditions, but corals are stuck in one place and can't seek out a better spot.

That said, unless you're going for acropora, montipora and other high-flow corals, there's no reason you can't run lower flow if your fish seem to enjoy it more. Clownfish tend to be weird and somewhat individualistic. I used to have a clown that seemed to love high flow and would actively seek out spots with high flow and swim directly into the current. My current pink skunk doesn't seem to care about flow in any way, shape or form, just goes where he wants to go. And the two clowns in my smaller tank tend to act more like yours, they mostly stick to one portion of the tank and don't explore much.

 

[theocorals537]

Greetings everyone, I am new to the hobby and seeking some input. I have a Red Sea XL300 (65g DT and 15g sump). It was fast cycled and has been running a month now. I have a Vectra M2 return pump at 40% for flow via Y pipe nozzle and an MP40 side mounted. There is a lot of rock scape with good caves and flow shield areas. I recently added 2 clownfish to the tank about 1.5 to 2" long. There is no coral in the tank yet. I originally had the MP40 on Reefcrest mode at 30% and over the past week it seemed like the clownfish were somewhat struggling with the current. They surfaced to get food fine but were not exploring the tank and just stayed mainly in a back corner of low flow. I have now changed the setting to Lagoon mode at 30% and notice that the fish seem to be moving around the tank more and swimming more at ease. Obviously Lagoon mode is less harsh then Reefcrest so I have a few questions:

Were the fish struggling initially because they were probably captive bred and not used to the flow? Would they eventually adapt or would they eventually die of fatigue and stress? I hope to begin adding corals which would probably consist of soft and LPS type corals which typically do ok with lower to moderate flow levels from what I have learned but what if the corals require something like Reefcrest to flourish better? I know some fish do better in high flow also then others but for a general reef community tank how do you balance the needs of the fish with the needs of the corals? Is it better to try and get the fish to adapt or get the corals to adapt to a specific flow rate?

Thanks in advance for any helpful suggestions.

I found that my mp40 are a lot more turbulent than I thought. My clownfish hate them , so I run them as low as possible to keep good flow for my corals. On one of my tanks the powerhead is turned down all the way on reef crest on a 40 gallon and it grows like weeds

 

[Lavey29]

Basically, yes. Fish can move and find spots in the tank where they're happy with conditions, but corals are stuck in one place and can't seek out a better spot.

That said, unless you're going for acropora, montipora and other high-flow corals, there's no reason you can't run lower flow if your fish seem to enjoy it more. Clownfish tend to be weird and somewhat individualistic. I used to have a clown that seemed to love high flow and would actively seek out spots with high flow and swim directly into the current. My current pink skunk doesn't seem to care about flow in any way, shape or form, just goes where he wants to go. And the two clowns in my smaller tank tend to act more like yours, they mostly stick to one portion of the tank and don't explore much.

Thanks for your insight.

 

[Lavey29]

I found that my mp40 are a lot more turbulent than I thought. My clownfish hate them , so I run them as low as possible to keep good flow for my corals. On one of my tanks the powerhead is turned down all the way on reef crest on a 40 gallon and it grows like weeds

Yes, I'm keeping mine down until I get the first beginner type corals and then I guess I will experiment a bit.

 

[Lavey29]

I found that my mp40 are a lot more turbulent than I thought. My clownfish hate them , so I run them as low as possible to keep good flow for my corals. On one of my tanks the powerhead is turned down all the way on reef crest on a 40 gallon and it grows like weeds

Do you mind telling me what intensity settings you are using and your tank dimensions? Just one MP40 or 2 in the tank. I have my side mount at 30% lagoon mode and the back mount at 15% tidal mode. Tank is 36x22x24.