Which Fusion Flow Linear fits my tank? A guide to the 230, 330, 430 and 470
Four sizes, and one measurement decides between them. This is the guide I wish I could hand to everyone who messages me, because the question is always the same and the answer is always a tape measure.
Fusion Flow Linear works on one idea. Instead of adding a second fixed pump to fight the dead spot behind your rockwork, you mount the powerhead you already own on a carriage and let it travel front to back across the tank on a rail. How far it travels is the sweep, and the number in each model name is that sweep in millimetres. A 330 moves your pump 330 mm.
The measurement that decides it
Measure front to back, inside the glass, in millimetres. Not the volume, not the length of the front pane. Fusion Flow mounts on the rear rim and travels front to back, so the width of the tank is the dimension that matters.
Take it at the waterline, along the line the rail will actually run, rather than at the easiest spot to reach. Then look at what is already in that path. Bracing, an overflow weir, a return outlet, a gyre mount or a feeding ring can all sit exactly where the carriage wants to travel, and any one of them can take 30 to 40 mm out of the usable run. Far cheaper to find that with a tape measure than with a delivered parcel.
Two more things while you have the tape out:
- Behind the tank. About 65 mm of the unit sits outboard of the rear rim, so you need that much clear space behind the glass.
- The rear rim itself. The clamp needs a clear stretch of rim to grip. On a reef-ready tank the central overflow box is usually the thing in the way.
What each size needs, and what it suits
| Model | Sweep | Clear opening it needs | Suits tanks measuring, front to back inside the glass | Price |
|---|---|---|---|---|
| 230 | 230 mm | 310 mm | about 340 to 440 mm, mostly all-in-one and nano tanks | £229 |
| 330 | 330 mm | 410 mm | about 440 to 540 mm | £279 |
| 430 | 430 mm | 510 mm | about 540 to 580 mm | £339 |
| 470 | 470 mm | 550 mm | 580 mm and deeper | £399 |
The sweep is always shorter than the tank is deep, because the unit carries its motor, pulleys and electronics in the 80 mm that sits over the water at one end. That part cannot be trimmed, so a longer sweep means a longer unit rather than tighter packaging.
Some real tanks
- A 500 mm wide tank, which covers a lot of the most popular reef-ready tanks in the UK, measures about 475 mm inside the glass. That is a 330, with roughly 60 mm to spare, and the sweep covers about two thirds of the span. The Red Sea REEFER 250 and 350 sit here.
- A Red Sea REEFER 200 or 300 measures about 551 mm inside. That is a 430, covering a little over three quarters of the span.
- A 600 mm wide tank is about 573 mm inside. Also a 430.
- A 643 to 650 mm tank is about 612 mm inside. That is where the 470 earns its place, because a 430 on a tank that wide leaves close to a third of the span unswept.
- An all-in-one such as the MAX E-170 has a rear chamber eating into the span, so the usable display depth is about 425 mm rather than the outside dimension. That is a 230. Measure the display section itself on any all-in-one, because no manufacturer publishes that figure.
If you land between two sizes
Two adjacent models will both physically fit a lot of tanks, and that is normal. The one to choose is the one whose sweep covers more of your span without the unit crowding the glass.
A sweep that is too short does not fail in any obvious way. It runs perfectly well and simply never reaches the front third of the tank, so the flow shadow you bought it to deal with moves rather than goes. If your measurement sits comfortably inside a range, take that size. If it sits right at the top of a range, take the next one up.
Going too long has a cost as well. The unit is physically longer, needs more space behind the tank, and the pump ends up travelling closer to the front pane than most people want. So size up because your measurement says so, not for the sake of it.
Tanks I cannot fit yet, and I would rather say so
Eurobraced tanks. Red Sea REEFER G3 models from the 425 upwards have a bonded glass ledge running round the top of the tank. The current clamp grips the rear pane front to back and cannot reach past that ledge, so I am not going to tell you it fits. A fixed-height clamp for eurobraced tanks is in development. If you have one of these tanks, message me before ordering and I will tell you honestly where that is.
Anything under about 340 mm front to back. On a tank that small, moving your existing pump to a better position will probably solve your dead spot for nothing, and I would rather say that than sell you something.
You keep the pump you already own
This is the part that separates Fusion Flow from simply buying a bigger pump. The unit carries your powerhead, so the flow arrives from a different place every few seconds instead of a fixed point on the glass. Your pump still sets the flow rate. The rail only changes where that flow comes from.
Mounting is either magnetic, using the magnet your pump already came with, with carriers for 40, 60 and 75 mm magnets, or a mechanical cradle with nothing magnetic in the water, currently for the Jecod and Jebao SOW range. Maximum pump thrust is 10 N, which is SOW-15 class. I have run it here with the SOW-4, SOW-8, SOW-15 and the D-D Funktion 10.
Setting the sweep once it is on the tank
You teach the two end points by hand. The motor switches off, you push the carriage to each end of the travel you want, and that is the sweep stored. Speed is a dial, and a tap of the button pauses it for feeding and resumes on its own after ten minutes, so a powerhead is never left parked in one spot. There is no app, no wi-fi and no account.
The rail itself is hardened steel, and it stays dry because the housing is a sealed channel with an overlapping cover and a drip edge rather than because of the grade of the metal. That geometry is the part that is Patent Pending, GB2619546.1.
Common questions
What if my tank sits between two sizes? Take the longer one if your measurement is at the top of the shorter model's range. Otherwise the shorter one leaves less overhang.
Does a longer sweep give me more flow? No. Your pump sets the flow rate. The sweep sets how far the origin of that flow travels.
Will I see the rail? Yes. It is a slim housing across the back of the tank and I am not going to pretend otherwise. What you get for it is flow that reaches the whole aquascape without a second pump in the water.
Can I run it under netting? You need to adapt your netting. But when you do, the 75 mm Feed Port Pro gives you a feeding hole in the mesh so you are not lifting the netting every day.
Can I run two? Yes, and they run independently of one another. Nothing synchronises them.
Measure first
Front to back, inside the glass, at the waterline, along the line the rail will run. Match it to the table above, check the rear rim is clear where the clamp needs to sit, and that is the decision made.
If you would rather I did it, send me your tank model and that one measurement, and I will tell you which size to go for. I answer these myself.
