What size Loc-line do i have?
It seems like a simple question to answer, but for anyone who has tried to figure this out, it doesn’t always seem clear. You’ll find loc-line in use in just about every saltwater aquarium and it’s used as a means of directing water flow on your return line. The hobby is full of all kinds of different attachments, accessories and nozzles that snap right on to the end of your loc-line, including our own Random Flow Generator, or RFG Nozzle.
When it comes time to choosing the right size it can be hard to tell what you need – especially if you only have access to one of the two most common sizes; 1/2” and 3/4” loc-line.
To make matters worse, if you were to try and measure your loc-line, you’re likely to get a measurement that seems confusing. For instance, the 1/2in loc-line is a little more than 3/4in across.
So, how can you tell what size you have? Here are a few tips to help you properly measure your loc-line.
The size of the loc-lin refers to the inner dimension or ID as opposed to the outer dimension or OD.
When measuring loc-line, use these numbers to determine what size you have.
1/2” loc-line
ID – approx. .675in, or about 17mm
OD – approx. .846in, or about 21.5mm
3/4” Loc-line
ID – approx. .925in, or about 23mm
OD – approx. 1.125in, or about 28.5mm
Compare the end to a Nickel (US).
A nickel is a good way to visually measure the end of a loc-line – just don’t stick it in your tank and accidently drop it. We would recommend you use this method out of the water.
If all else fails – stick your finger in it!
It’s not the most exact method, but if you can fit your index finger in it, or at least most of the way in, it’s probably a 3/4in lock-line. If you can’t and the opening is too small, then it’s probably the 1/2in variety.
1/2” loc-line
1/2″ loc-line is pretty small, so you may not be able to fit your index finger in.
3/4” Loc-line
You finger will likly fit at least most of the way in – just don’t get it stuck.
We hope this quick-tip helps you figure you your lock-line. and the next time you have to measure loc-line, you can do it like a pro.
Happy reefing!
– VCA
What Type of Nozzle Should You Attach to Your Loc-Line?
Well, that’s easy – a Random Flow Generator Nozzle of course.
Recent reviews
3/4in Random Flow Generator - RFG075by Stephen Mertens
1/2in Random Flow Generator - RFG050by Darrin Sevitz
3/4in Random Flow Generator - RFG075
1/2in Random Flow Generator - RFG050
I would like to replace my return nozzles on my 28 Gallon JBJ Nano Cube. Could you tell me if any of your nozzles would fit and which ones? Also, I used this overflow kit for 3 different aquariums in my home.
https://www.amazon.com/gp/product/B0002DJAZQ/ref=oh_aui_search_detailpage?ie=UTF8&psc=1
The returns are loc-line but I don’t know what size. I would need 4-6 return nozzles; could you please tell me what size for this scenario as well?
Thank you!
Hi Toby,
The JBJs usually have the 1/2in loc-line slip adapter. If that is the case with yours, then you would want pair that with the 1/2in RFG Nozzle. You may also want to add a few pieces of loc-line to give you more flexibility when aiming the nozzle.
As for the overflow kit you linked – it looks to me to be 1/2in loc-line as well but, but the listing doesn’t have any specs, so it’s hard to know for sure. I would suggest try measuring the loc-line using one of the three methods above.
I just purchased your nozzles from watching you on Rico’s stream, cant wait to get them.
Hey,I’m about to order a 2 pack of the random flow generators, and just wanted to let you know I heard about these from Rico’s Reef youtube stream, thanks!