Flow question

Ok, so I am setting up a 240gal tank and trying to figure out a good amount of flow. I have heard everything from 2X to 50X an hour turn over. I currently have enough pump and powerhead equipment to turn about 37X. The tank will start off as FOWLR, and eventually over time turn to a full reef setup. I need your opinions on the amount of flow and WHY. There has to be a reason to the crazy gap in flow rates.

 

Kdneo

its a good question

3 things IMO that really matter - there could be more

1 - if you are running a Berlin type system where the majority of your biological filtration occurs on your live rock, then you do need a good amount of flow to continually carry that nutrient loaded water around the tank, so the bacteria colonising the rock can process the wastes

2 - SPS corals, they are from upper water levels in nature and as such are conditioned to the buffeting they get from daily water movement , SPS corals dont do well if sediment/ detrius settles on them, so good water movement is required to keep them free of debris

3 - dead calm areas in the tank are a haven for cyno bacteria and other nuisance algaes so we need to make sure there are no dead areas in our set ups of possible

if you keep Softies and LPS for example you might struggle keeping them happy or finding a suitable place for them in a tank with 50X turnover

I have 42X in mine but have achieved it using 5 x powerheads so I have 3 larger ones looking after upper half of tank and 2 smaller ones looking after the lower half
so a compromise is reached and my LPS dont get buffeted

Steve

 

Water Movement In The Aquarium

It's not new information, but its usefulness will never grow old. This article pretty much says it all--

 

That was a good read! Anyone wanna buy a Tunze wavemaker? So it looks like anywhere from 10-20 is good and that will work for even nice stony pieces huh? So I guess I can get rid of a few of the powerheads I have. Great info again, this is why I hang out here!

 

10-20x is pretty light. I run between 35 and 40x in my 100G SPS dominated reef and thats with 330 lbs of Southdown sugar sized sand that does not blow around at all. Heck, you get 12x with a single K4 powerhead, definitely not enough.

 

I have 230lbs of dry sand, 240ish lbs of base rock. I calculated with the equipment in the garage that I have just over 9000gph. Keep in mind the tank is not setup yet, still gathering info and research on all the stuff I have and trying to figure it all out. Would you suggest using all the powerheads and pumps that I have and going with the full 37X that I have?

 

I would - every time I added a power head (I started with 2) I worried that my tank looked like a washing machine on spin cycle - but the corals adapted, I added another, they adapted again

I would not go backwards on mine now, and yes I am still considering moving forwards - increasing the flow ( Im also considering trading in my softies for additional SPS)

Steve

 

You need to consider a few things first. How many and what size pumps and powerheads are we talking about? Every piece of pumping equipment you add has a heat load and electrical consumption associated with it. A couple very efficient powerful powreheads like the Koralia 4 or the newer Magnum series is a better option than 5 or 6 MJ1200 powerheads. Look for powerheads that move a bunch of water in a wide dispersed flow pattern at a low wattage, very efficient. Unmodified MJ powerheads move much less water and draw more power as do others like Penguins and AquaClears. I have tried two different MJ modifications and was not happy with either one, they vibrated and just had problems. I do use one of the mod propellers in a K4 though and it increased the flow quite a bit.

Use as few pumps and powerheads as possible yet will still reach the flow you want. My tank is a 100G, 60"x18"x23" high, I have a K4 in each back corner, a OR 3500 return pump into a LocLine return basically in the middle of the tank and a closed loop with another OR3500 through a Oceans Motions Squirt two way with the returns in the upper back corners. I can also add a K3 in the back center to keep stuff from collecting behind the rockwork if needed. The closed loop gives me nice random flow. I recently purchased a ReefKeeper Lite and put the two K4s on the wavemaker function but am not happy with it, the chatter on start up so I need to look at different powerheads for that. The wavemaker function is nice its just the powerheads won't take it.

I like the idea of random flows so all pumps are not running 24/7 thus lower power consumption, less heat gain and better random circulation patterns since both the closed loop and wavemaker may or may not be running at the same moment so flows are always different, never the same.