i am plumbing my tank right now and im wondering does anyone point their outputs in the same direction rather than having them fight each other. i know most reefs have linnear flow rather than chaotic(unless on the reef crest). so would it work to have the water in your tank spinning like a tiolet rather than fighting itself. i would think you would have more total flow with all the outputs working together. i know it wont work perfect in a square tank. any thoughts? by the way im not stacking the rock against the back im going to have just one or two islands.
chaotic vs linnear flow ?
- Thread starter jamielind
- Start date
mr.wilson
.Registered Member
Paul from Oceans Motions is a strong proponent of circular flow dynamics. The only negative aspect of circular flow is the possibility of constant flow patterns. Corals require a variation in flow direction to achieve interesting shapes and adequate availability of food. Wave makers and surge devices will solve this problem.
I recently set-up an 8' tank that had limited flow compared to todays standard (13 times the volume of the tank per hour movement). It is functioning very well with only one effluent at the surface running one direction and two parallel closed loop lines running the opposing direction at the bottom of the opposite end of the tank.
The circular motion allow for only one dead spot, and seems to aid flow of the closed loop intake and overflows. It's easy to forget, but the pump intake and overflow represents an equal volume of water per hour.
With proper flow dynamics, the 13 times per hour is equivalent to 26 times per hour, as the pump is part of the wave action.
I find that systems where water hits opposing flow, it dissipates and detritus settles. Steady laminar flow from the bottom up will assure detritus and food suspension for feeding and removal.
Another system that I've found to work well is a series of three effluent ports positioned in a spiral (circular) pattern on the bottom of the tank. 45 degree elbows direct the water slightly upwards so the water flow works in conjunction with each corresponding outlet.
Rockwork invariably foils these flow patterns, but you have to balance form over function. Drilling holes in the rock to allow for free flow helps.
The practice of directing multiple effluent downward towards the rock formation is counter productive. It doesn't promote good gas exchange by moving water from the bottom to the top, and it pushes free-floating matter down, rather than keeping it suspended.
The only problem with good, upward, laminar flow, is that it works too well. Your tank can look like a snow globe, as detritus never settles. Mechanical filtration can be implemented to solve this issue.
I recently set-up an 8' tank that had limited flow compared to todays standard (13 times the volume of the tank per hour movement). It is functioning very well with only one effluent at the surface running one direction and two parallel closed loop lines running the opposing direction at the bottom of the opposite end of the tank.
The circular motion allow for only one dead spot, and seems to aid flow of the closed loop intake and overflows. It's easy to forget, but the pump intake and overflow represents an equal volume of water per hour.
With proper flow dynamics, the 13 times per hour is equivalent to 26 times per hour, as the pump is part of the wave action.
I find that systems where water hits opposing flow, it dissipates and detritus settles. Steady laminar flow from the bottom up will assure detritus and food suspension for feeding and removal.
Another system that I've found to work well is a series of three effluent ports positioned in a spiral (circular) pattern on the bottom of the tank. 45 degree elbows direct the water slightly upwards so the water flow works in conjunction with each corresponding outlet.
Rockwork invariably foils these flow patterns, but you have to balance form over function. Drilling holes in the rock to allow for free flow helps.
The practice of directing multiple effluent downward towards the rock formation is counter productive. It doesn't promote good gas exchange by moving water from the bottom to the top, and it pushes free-floating matter down, rather than keeping it suspended.
The only problem with good, upward, laminar flow, is that it works too well. Your tank can look like a snow globe, as detritus never settles. Mechanical filtration can be implemented to solve this issue.
Have you been reading the series on water flow published in the Advanced Aquarist magazine (http://www.advancedaquarist.com/2007/1/aafeature)? It makes the case for 'gyres' (circular water movement).
Similar threads
