Your rule of thumb for "enough" flow

[enveetie]

How do you know you have enough flow? Or what makes you feel comfortable with your flow? Besides obvious answers like, "good results after x amount of months", what indicators are you looking for as you set up your flow patterns?

Looking for polyp movement? Polyp extension? Fish plastered to the glass? Water sloshing over the rim?

I always second guess my flow. 2x pp-15's and 2x pp-4's on the back wall of a 36x36 tank. It's turbulent; lots of alternating wave action. It is A LOT. Yet I still second guess my flow. Heck, maybe I have too much flow. So other than waiting weeks and months to compare results, how do you "know"?

 

[Gweeds1980]

Obvs depends on the animals your keeping... for acros keep adding to the flow until you're blasting flesh off and then scale back a touch...

In a general mixed reef, like mine, I'm lucky enough to have a tank big enough to have two distinct flow zones... really high one end with two cp55 gyres on max, disrupting each other's flow and one at the other end turned down a bit... LPS at one end, SPS at the other and softies into the lower flow areas towards the bottom.

 

[Gweeds1980]

Oh, and to answer the question... PE is my indicator, if they're not happy PE will be affected in just a few hours ime.

 

[LobsterOfJustice]

Put some flake food or frozen brine/mysis into the tank... none should settle on the bottom. Generally if the flow is good enough to keep food (or detritus/fish poo) suspended until it gets eaten or makes its way to the overflow, then the flow is good enough for corals as well.

 

[jda]

I have sand. I want to be right at the point where the sand does not move.

If your fish eat a lot and are still skinny and unhealthy looking, then they are stressed from too much flow.

 

[lolgranny]

I throw in some frozen food and see how the flow is. I dont want any dead spots and i also dont want flesh peeling off acros or weird growth for them. Over the years they will want more flow but they dont need to be blasted when they are little guys

 

[Reefltx]

I have zoas at the bottom and gsp for flow indicater and they’re pretty shaggy. I have decent flow.

 

[cFloor]

In my tank, which is 100% acropora, I had to remove my very coarse sand because it would get blown around by my MP60s. I am looking for strong, random, indirect flow throughout my tank. I am a big fan of pulsating flow.

 

[Salty1962]

In between a sand storm.

 

[AdamNC]

When your sand starts blowing around then back up a hair. My sps are growing nicely and my sand bed in the front is always moving a little.

 

[zsuzsu]

when my fish are pinned to the glass i back er down a snit

 

[Coronus]

When every single polyp on every single acro or any other coral in the tank is moving.....thats when I felt I had enough and still added more.
True story!! Tank turnover volume is around 110 gph. Trick is setting it up so sand holes dont form.