how much water movement do I need in my 90 gal tank

Hey Gals and guys,

I need some help with water movement. I wanted to know how much water movement in terms of GPH do I need to asure that most of my detrius is scooped up into the water column and that no dead zones exist in my tank. I would like the detrius in my water column to be sucked up by the overflow and into my sump where my prefilter and skimmer can consume them. The rest of my detrius can be eaten by my detrius crew and other live thingys in my substrate. Also, if dead zones are eliminated based on how I place my powerheads then can someone tell me or show me via a diagram how I should place my powerheads within my 90 gal tank, any help is appreciated thanks alot, people. Have a good night.

Tyslin

 

Hi Tyslin,
When you talk about water movement...it is better to look at it in terms of positioning rather than GPH IMO!
It is best to have the powerheads positioned in a way that the water flow created by the powerheads blows the water directly on the glass and basically banks off it creating more water movement to a greater area that if it was positioned differently than that!
Alot has to do with the amount of coral, types of coral and structures(ie. live rock) that the water has to penetrate in and through!
The flow of the coral polyps is a pretty good determinent of a good water flow! Try not to have too strong a current into your substrate as it will cloud your water and spread the substrate onto your rock or other corals as I have found out!
One last thing: A good water flow will suspend detritus longer in your water column for maximum removal by your skimmer!!!!!!
Also, it is very beneficial to position a powerhead towards the top of your tank so that the air/water interface will remove excess CO2 and add DO(dissolved oxygen) to your water.

 

Thanks Coral,

Hey just wanted to let you know that my skimmer is in my sump underneath my tank. So what will happen to the detrius in the water column if the skimmer is not present to pick it up in the main tank.

Also,.. so your saying that my powerheads should be pointed somewhat towards the surface of the water but not completely?.

 

If you don't have a skimmer, some of the detritus/DOM etc. will be absorbed by filter feeders, corals, bacteria etc. The rest will remain suspended in your water column or settle between your live rock, settle in your substrate and eventually through diffusion and advection sucked into your substrate.
For the powerheads, if you place one powerhead so that it makes the water at the top of your tank ripple, it will help aerate your water and remove some CO2!

 

So if I have detrius eaters like nassaarius snails, tiger cumcumbers, conchs, and others I shouldn't worry about the detrius on my substrate right?

And the other detrius absorbed by filter feeders, corals, bacteria etc that's good as well right?

what happens to the detrius that settle on my live rock?

I guess the best question is,...is it better to have the skimmer on the main tank or sump? sound like the main tank to me.

Just want to know these thing Coral, thanks for your info it's really helping me out.

 

Ok,
First off, you still have to worry about the amount of detritus on your substrate because it will change your water quality! It is beneficial to have those bottom dwellers though...
Yes it is very good for filter feeders, coral and bacteria to have detritus/ dissolved organic matter which they will feed on as nitrates and phosphates to some degree! Just don't want to have too much as this affects your water quality.
As for the skimmer, it doesn't matter where you have it IMO, though it makes more sense to be in your sump and out of the visible eye, as it represents one less thing in your main tank. The water circulates throughout your whole system...remember!
Glad I can help!

 

Your good Dude, thanks alot.

 

It's my job! hahaha, just glad to be able to help...I'm learning as I go as well!