Water Current

[sean_p_f]

I am wondering what your answer is to this question.

"Is there a such thing as to much current?"

I have been told yes and no so i am trying to get a better idea.

[IBMGeek]

I think you need a balance. Enough current where theres no dead spots and ridding corals of chemical buildup (slime, mucus whatever it is they produce) on them, but not too much where its kicking all your sand up. Unless you go barebottom then I guess you can have all the current you want.

[coral reefer]

It depends on your types of coral etc.!
They require different water flow intensities...and if the right one is not achieved, maximum results will not be evident and possibly lead to the demise of corals and Tridacna Clams in particular!

[IBMGeek]

Yeah I forgot about that. SPS are known to require tons of indirect flow. And then you have more sensative creature like coral reefer mentioned. So you need to keep that in mind.

[wastemanagement]

only if all your live rock and coral end up in a heap at one end of the tank!!! then you might have to much flow

After looking at you tank specs I would say that you could have enough flow to sustain a tank that requires low to moderate flow.

To give you some referance my tank is a 55g and with all my l/r makes it about 35g and I have 4 maxi-jet 1200's on DIY wave maker all fitted with hydor deflectors the return from my skimmer and a 304 flurval with no media.

With this I find that I have no dead spots in the tank just some low flow areas(damn)

I have Mushrooms, colt, xeinia, toadstools, pagoda, open brain,and a goniopera and some others what I cant think of right now.
but they all do fine at this time and Im looking to add more flow via a sump return in the near future

[Jadefox]

Originally Posted by sean_p_f

I am wondering what your answer is to this question.

"Is there a such thing as to much current?"

I have been told yes and no so i am trying to get a better idea.

This is a great question. I am in the process of running a biotope-specific tank--that is a tank representing a very specific habitat, and that habitat is defined by very high flow. So perhaps I can shed a little light on this question.

The complete system is 240-gallons, and the main display tank replicates a nearshore reef off the coast of Hoga Island where the current really rips. Not all of my flow is created by the return pump, as I have a CLS in the 135-gallon display tank as well, but I do have a powerful return pump that (once head pressure has been calculated) creates 2400 GPH flow rate. Some people would say this is too much flow moving through my sump. My skimmer is an AquaC EV-240 with a Mag 18 (1800 GPH), which already overdrives the skimmer. In essenence, I am passing unskimmed water back to the system, which some people claim is a waste. So there is one argument you may hear about too much flow--if your return pump outperform your skimmer pump.

In the tank itself, I have a CLS with an OM4, which returns water through two returns on the back wall at the top of the tank and then through two returns in the front of the tank on the bottom. The two returns from the sump are mounted in the top front corners of the tank, and there is a spray bar along the entire back bottom wall. This is a lot of flow--I would estimate that I turn over water about 40+ times per hour, but that is what I was looking for with this set-up. Would this be the right flow for all species? Absolutely not. So to get back to your initial question, it depends on what you are going to keep in the tank IMO based on the fact that there are naturally occuring biotopes where the current really rips.

If you want to see more about my system, you can check out the series of articles about it. The first one is posted here:

Biotope-Based Marine Aquaria - Interconnected Biotope Tanks Improve Overall System Stability

I'd love to keep this discussion going!

[Otty]

I keep a SPS domane tank and I have 5,800 gph HammerHead running a OM 4-way plus I have another 5,800 gph HammerHead returning water from the sump. Some may say this is too much flow but in my own opinion I think I need a little more. As long as your not blowing sand up all over the place then you should be ok on flow. Just think of how the waves come in on the ocean.

Before this thread is over you will hear about 10 different opinions on this so just take what you want out of it and trash the rest.

[ReefSparky]

As someone said, the only way you'll have "too much" flow is if your LR and corals end up in a heap in the corner. IMO, as long as you don't have a sandstorm or visible coral damage, you can never have too much flow.

[Jadefox]

Let 'er rip!

...one thing to consider is how you get that flow. Many commercial aquariums that are very large use a massive return pump to turn over the tank 40+ times per hour. Many hobbyists and smaller systems employ a closed loop system to create a lot of the in-tank flow and keep the return pump matched to the skimmer at 10x. Also, if you have a UV sterilizer on the return line, you'll want a quality bypass if you're cranking as much flow as many of us do from sump to display tank.