I have a Salamander Keel Hauler tow belt. After one year of use, the aluminum carabiner doesn’t operate anymore. I rinse my gear in fresh water after each use, but apparently the saltwater doesn’t agree with it.
Has anyone else had this issue? Are some aluminum 'biners more corrosion resistant than others?
I sent an inquiry to Salamander, and the response I got was along the lines of “yeah, our supplier stopped carrying the stainless ones so we use aluminum now.”
Do the rest of you get longer life out of your anodized aluminum 'biners?
On the upside, I found a stainless biner made by Wichard (sailing hardware company) with an enclosed eye, and with no notch that catches lines. It cost about 1/3 the original price of the entire tow belt. 
nope
my aluminum ones never last long. Have had better luck with stainless steel ones from home depot.
Stainless steel
I have a contact tow line with an aluminum 'biner which is constant maintenance.
If you want to spend a little more money but get light and durable, try the better climbing 'biners. No notch to sand down like some of the ones from marine stores.
notch
Actually the replacement one I got from a marine store has no notch. The hook end has a slight bulge, and the gate surrounds that bulge, so it still engages like a notched biner. (I also got smaller sized ones for my contact tow line that stays on deck). The weight of these is considerable though. I’m going to need to add a sizeable float if I want the end of the line to stay near the surface.
Re the better quality climbing biners - are you saying that some of those are more corrosion resistant? Is there a brand or particular alloy to look for?
I assume you’re referring to…
…“keylock” style 'biners. All climbing 'biners have either a notched gate or a keylock, but keylock 'biners are definitely better for paddling use. However, they’re not any more corrosion resistant than standard 'biner, so they need to be rinsed and lubed regularly.
Nate, you can bring your old 'biner back to life by working it in hot water until it moves freely, then using a lube like Boeshield or CorrosionX on it.
The pretty ones 
I have an unfortunate taste for the ones in pretty colors from EMS that cost 12 or so bucks… have noticed the aesthetics more than the metal mix unfortunately.
thanks brian
Do I find those lubes at climbing stores?
The red anodized body of this biner looks perfect. It’s the silver gate that isn’t holding up. Maybe that part isn’t annodized. Around the hinge the gate is corroded enough that the gate can barely be pushed open and closed.
I’ll see if I can free it up.
BTW, I just got an email back from EMS (where I bought the tow rig) and it sounds like they may send me a biner that they think will hold up better. A great improvement over the fairly dismissive response I got from Salamander.
climbing 'biners
In my “other” job, I manage product in a store that sells a lot of climbing equipment.
In my “other other” job, I teach kayaking.
I am always surprised by the number of people who have climbing 'biners for use on tow belts or contact tows. Around here, a lot of the kayaking is on fresh water, that might be one reason why. But when asked, a lot of people admit to experiencing problems, especially when having been in salt water.
Climbing 'biners were never engineered to withstand the corrosive environment of salt water! Aluminum corrodes quite easily, and will become heavily pitted after awhile. Sure, you can wash it regularly. Easier said than done, but it is certainly one way to deal with the issue.
There are two things to look for when using climbing 'biners. One is anodizing- yeah, the more expensive, brightly colored ones. The other is to look for wire gates. Regular gates use an internal mechanism of a spring an a small lever mounted with the affixing pin. Rarely are those parts made of high grade stainless; once they get corroded/contaminated, the biner is worthless. Wire gates can also corrode (not the best grade of stainless), but can usually be worked back into a functioning mode if corrosion takes place. Problem is, there are no wire gated 'biners that are keylock. This means that one should file off the nose on the hooked portion where the wire nests. Don’t worry, the resulting 'biner will be more than strong enough.
Now for the funny part. The people who introduced wire gated 'biners to the climbing world were inspired by the wire gated stainless steel 'biners used in the yachting world!
Boeshield is readily available…
…at hardware stores, home centers, marine suppliers, bike shops, etc. CorrosionX is harder to find, but marine suppliers should have it.
I’ve taken a 'biner that was corroded to the point that the gate wouldn’t move at all and got it back to perfect working condition. I wouldn’t use it for climbing, but it’s fine for kayaking purposes. It took some time to do it (an hour or so), but I took it as a challenge and had fun with it.
Wire gates ARE better…
…but the internal parts in climbing 'biners ARE resistant to salt water. I’ve never had a problem with the springs or pins in a 'biner. As you said, the problem is corrosion of the aluminum. While you should NEVER use a corroded (or formerly corroded) 'biner for climbing, for the small loads they see in kayaking use, it doesn’t matter. They are many times stronger than necessary, which is why you can file off the hook and they work fine.
'Biner Maintenance
To be a little more serious - Between two short tows, the towbelt and the paddle 'biner I have a mix of stainless and aluminum/similar alloy 'biners. We spend some time in salt water each year, but don't live there. So most of our paddling days each year are in fresh water.
All of the non-SS 'biners require minor attention once in a while, and even the SS ones needs to be cleared of sand and grit once in a while.
But the worst maintenance I am talking about is a half hour soak in water and some dishwashing detergent, once in a while. Or opening and closing the 'biners if we get caught in some rain. It's not labor intensive stuff even when I have to up the frequency for our salt water time. Maintaining the dry suit zippers in salt water is more work.
Doing this, I haven't had the problems that Nate reports. The one on the end of the belt-mounted short tow has been with me for a few years now, and while there is some discoloration nothing has happened that makes it not operate. The climbing one has been on my belt for this whole season and so far looks brand new.
What I do appreciate about the climbing 'biners is how light they are - so that is my preferred choice for my tow belt. The SS ones just can't compete on that convenience factor.
Climbers Don’t Lube
Climbing gear is generally not lubricated or is lubricated as minimally as possible. Lube picks up dirt and climbing is all about dirt, rock, and stuff that clogs gear.
Look at wire gate carabiners. They might not have the same problems as solid gate carabiners since the gate operation doesn’t rely on the same type of hinge or spring mechanism.
Dave
You’re correct…
…but lubing is necessary to prevent corrosion if you use them in salt water. Wire gate 'biners are better, but they’re not immune to corrosion, so lubing is probably still going to be necessary.
Good post Celia
As you state, the maintenance is really no big deal.
One day later
I recieved a nice Petzl biner from EMS as a replacement, free of charge. The gate and body are both annodized.
From the comments here it sounds like a good-quality biner like this one will hold up just fine in saltwater, with some minor maintenance.
It should hold up, but…
…the pivot area is still subject to wear and the hole for the pivot pin may not be anodized, so keeping it clean and lubed is still important.