Aquarium Flow: High Flow versus Random Flow

[happyhourhero]

Random high flow. I am a firm believer that ALL corals like high indirect flow.

 

[NY_Caveman]

I say high, random flow in most cases. Remember too the rock work has a lot to do with this as well. A smart aquascape can enhance the flow pattern you want and help create areas of more random flow as well as zones with lower flow (as @Porpoise Hork mentioned). A poorly planned aquascape can lead to terrible flow no matter how high or random you set it.

EDIT: I voted random because in my experience the randomness is usually more important than the level, although both are important.

 

[cracker]

later comment.

 

[Flippers4pups]

Random and as high as all your corals can handle and be healthy. Mixed tanks with SPS can be a challenge, but from my own experience, it can be done and done well.

I'm going to add some more wave makers soon to "random" it up a notch.

 

[DarthSimon]

What about mixed reefs? I can’t keep all mine as happy as I’d like them to be so because of the sps I have the water is a little more turbulent. The torches don’t mind but the frogspawns and hammers don’t care for it nearly as much. Everything else is fine so I leave it there. I’ve come to the conclusion that you can’t make them all happy. Oddly enough the other euphyllia’s still grow great. They just don’t come out as big as when there is slower flow.

I find with my power heads up higher, currently using Gyre 230's you get great flow in top and middle sections, and lower quadrants aren't as rapid. Which is great for SPS up top and as you go down in tank better for LPS and softies...

I used to use Vortechs and found they didn't evenly distribute flow throughout the entire aquarium.

 

[Servillius]

I’m gonna vote with Paul B and against the tide (sorry, I’m so sorry. One more pun and my wife will have me beaten. Sorry, I don’t know if implied puns count.

High flow is more important than random flow and lots of high flow is best. Random flow or at least multidirectional flow is probably better for avoiding dead spots, but you want to break into the boundary layer as much as possible and that’s all about rate over time.

 

[Servillius]

One random thought on flow. Every pump, no matter how you set it, is always shooting water at the pump as much as away from it. You want changes in water movement, some pumps need to turn off some of the time.

 

[Forsaken77]

My main goal, because I only have a Xenia coral for nutrient export, is to keep detritus suspended so it goes into the overflow. Because of this, my Xenia no longer pulse because there's plenty of flow past them.

I bought a reef-ready tank so I can utilize the lower vents on the overflows. They make a HUGE difference in sucking up detritus. I honestly don't know how people just go with surface skimming. So my flow is more about getting the lower water to flow past those vents.

But I think it's more than just random or high flow. I think it should be tailored to each tank based on the needs associated with the inhabitants. What may be good for the corals may not be ideal for the fish (getting blasted all the time).

I think your suggestion of more, lower flow powerheads is better than just blasting water everywhere.

 

[SciGuy2]

Diffuse, random, high flow is the ticket. Also, maximize gas exchange.

 

[WVNed]

So lets try 100% and 60% on the gyres and add the PP-15 at 100%. I am trying to hit the lights. No fish have flown out of the tank yet.

If I de-rate the pumps because none of them are running at constant speed it is only about 30x tank volume.

 

[MJC]

My choice isn't in the poll.....I say both high and random flow is my vote.

After seeing a local reefers 180 fully stocked with stick colonies....with I believe 12 powerheads..YES, TWELVE.....and Dana Riddles MACNA talk from 2016, I increased my powerheads from two MP40's to four MP40's and an MP10....flow is the answer....and I'm considering adding more. Here are the powerhead locations in my five foot tank.

If you wish to just see the discussion on flow only from Dana, it starts at about minute 24:45

Thank you for posting this video I somhow missed it and thought it was very knowledgeable.
IMOP Everyone should see it.

 

[chefjpaul]

Just watch the video of the Aquaforest display.

 

[ArowanaLover1902]

Personally I believe that with a well planned aquascape, random flow is unnecessary, for example, i try not to mix corals, instead keeping each coral in an area that is great for it, which makes sense, a reef isn’t 1 single environment, it’s countless. I try to clump my corals as much as possible, keeping my sps and similarly minded lps in certain areas while keeping my lps and softies in other areas. It has a great effect on their growth.

 

[maroun.c]

Both have their advantages. Random is good to slowly move polyps and water around them butntry not tonblast corals non stop... Strong flow is needed to pull detritus out of the inevitable dead spots. I'm.use the following:
Seaswirls on my return line where my return Pump pushes around 3000 gph effective. Those provide a strong linear and redundant flow as the seaswirls rotate the output.
Vortechs which are the best for random flow, I have them.on a program on reeflink so mode changes during the day.
Overrated gyres which provide a nice strong linear flow that still changes on and off...
Looking at corals they get different types of flow anytime which can be very strong as times. The areas that still get a bit less flow host chalices Acans....

 

[stevieduk]

i am never sure about the "corals do not like current from one direction" statement. Like someone said earlier ,if you dive on a reef the current will take you and you dont really need to swim, but , if you think about it , that current will flow in one direction for 5 hours then slow to nothing, and flow the opposite way for five hours as the tides change,. So,in a way , corals do get water flow from one direction , but only for a few hours till it reverses

 

[Metcho]

High random flow. I have 3 Jebao RW-8 on W1 turned all the way up about 6” under the water one on either side and one on back wall all facing upward. Also the return pump a jeboa 12000 turned all the way up through two flow excelirarors on either side of the tank it’s 4' X 2’ X 2’ tank if anyone was wondering the dimensions. Sps dominate and all polyp extension and loving it high and random. Hawaiian black sand on floor and not moving to much. It’s more like the crushed coral type instead of sugar sand.

 

[vetteguy53081]

With so many new pumps offering random, Pulse and gyre flow...... Random seems to be the way to go. I can say for myself,,,,,,, with 30 years of experience, I had difficulty in keeping and acro(s) alive or thriving. I bought the icecap 3K and went to puls and turned down my MP60 units to lowest setting. Everything in the tank is full, acros alive and well and less salt creep !!

 

[User1]

high + random = chaotic. More chaotic ..... more better.

I don't really like the 'gyre' pumps as they tend to create laminar more than chaotic flow. Strong laminar flow (constant power-head pointed at a coral) is not a good thing.

Chaotic is a good word. With my Reef angel and a pair of RW-4's I could randomly tie them to storms via the controller and spin them up to 100% causing chaos. I've not found that possible with the limited "smart" controller on the Gyre's XF250's. However, it is possible to get some chaotic flows for a hour or so when using the A and B paddles. My issue with the Gyre's is really the limited functional use of the controller it ships with.

But to your point - I like more of the chaotic random flows myself.

 

[User1]

With so many new pumps offering random, Pulse and gyre flow...... Random seems to be the way to go. I can say for myself,,,,,,, with 30 years of experience, I had difficulty in keeping and acro(s) alive or thriving. I bought the icecap 3K and went to puls and turned down my MP60 units to lowest setting. Everything in the tank is full, acros alive and well and less salt creep !!

I don't know what size that tank is but I like your rock and coral placement. While at first glance it would appear to be a pile of rubble but that is really misleading. Thanks for that picture - I like it.

 

[vetteguy53081]

Thank you. Have mine scaled more like an ocean floor than aquascape

I don't know what size that tank is but I like your rock and coral placement. While at first glance it would appear to be a pile of rubble but that is really misleading. Thanks for that picture - I like it.