Is "it's just surface rust" an acceptable answer?

[JoshKReef]

Without getting into specifics, I have a piece of equipment that is fully submerged full time in my tank that I noticed some rust on. It is a higher end piece of equipment, and still under warranty. While doing my normal maintenance on the product, I noticed some rust on it, so I sent in a support ticket. The answer I received was this:

"That is just surface rust and should not be an issue. We would recommend cleaning the units in a 50/50 solution of warm water and vinegar for a few hours. If it is still an issue for you, you will need to send the units in for service before they can be exchanged."

I'd like some info on what this could possibly leech into the water, and maybe some help constructing a reasonable response. I personally don't feel this is a good answer, considering this is a high end piece of equipment still under warranty.

@Randy Holmes-Farley I was hoping you may have some input on how this would impact any of the tests which you sent your water away for.

 

[KMench]

Oh my. I literally got the same response yesterday! Here's how it started "That small amount of rusting wouldn't be unusual, and also we have the following cleaning method that you may find clears that all up for you. " I'm going to try the vinegar solution next time I clean it and see how it goes.

 

[JoshKReef]

Oh my. I literally got the same response yesterday! Here's how it started "That small amount of rusting wouldn't be unusual, and also we have the following cleaning method that you may find clears that all up for you. " I'm going to try the vinegar solution next time I clean it and see how it goes.

I have this issue with two of the same product (purchased together), and my cleaning routine is a vinegar soak every two months (I do 1 a month so my tank is never without a power head running).

 

[KMench]

I normally just pull mine out and brush them with a soft bristled toothbrush after disassembly. They are probably only 8 months old and one has the rust while the other doesn't.

 

[Porpoise Hork]

One thing to keep in mind when dealing with anything made of steel, be it stainless or otherwise. When placed in a saltwater environment sooner or later it will rust. The extremely corrosive nature of saltwater will cause even the highest grade stainless steel to show signs of deterioration. Gold is the only metal that does not react to this type of environment. The only way to prevent this is to apply a hydrophobic protectant to what ever is being immersed in the tank. I have seen multiple products capable of doing this one comes to mind called NeverWet. I have seen similar products to this stuff keep corrosion from developing even when immersed in a salt water environment for well over a year. Now can your item be treated? depends on if it has moving parts or not. If not, then yes. If so then possible depending on the components.

 

[Randy Holmes-Farley Verified Community Expert]

Without getting into specifics, I have a piece of equipment that is fully submerged full time in my tank that I noticed some rust on. It is a higher end piece of equipment, and still under warranty. While doing my normal maintenance on the product, I noticed some rust on it, so I sent in a support ticket. The answer I received was this:

"That is just surface rust and should not be an issue. We would recommend cleaning the units in a 50/50 solution of warm water and vinegar for a few hours. If it is still an issue for you, you will need to send the units in for service before they can be exchanged."

I'd like some info on what this could possibly leech into the water, and maybe some help constructing a reasonable response. I personally don't feel this is a good answer, considering this is a high end piece of equipment still under warranty.

@Randy Holmes-Farley I was hoping you may have some input on how this would impact any of the tests which you sent your water away for.

It may be a good answer from an engineering perspective relating to device failure, but not with respect to leaching of metals.

Do you know the type of metal?

 

[Randy Holmes-Farley Verified Community Expert]

Oh my. I literally got the same response yesterday! Here's how it started "That small amount of rusting wouldn't be unusual, and also we have the following cleaning method that you may find clears that all up for you. " I'm going to try the vinegar solution next time I clean it and see how it goes.

The vinegar may remove the surface oxides, but unless it is an aesthetic (looks) concern only, I can't see how that eliminates other concerns, such as release of metals to the water.

 

[JoshKReef]

My guess is some kind of stainless steel?

 

[Potatohead]

One thing to keep in mind when dealing with anything made of steel, be it stainless or otherwise. When placed in a saltwater environment sooner or later it will rust. The extremely corrosive nature of saltwater will cause even the highest grade stainless steel to show signs of deterioration. Gold is the only metal that does not react to this type of environment. The only way to prevent this is to apply a hydrophobic protectant to what ever is being immersed in the tank. I have seen multiple products capable of doing this one comes to mind called NeverWet. I have seen similar products to this stuff keep corrosion from developing even when immersed in a salt water environment for well over a year. Now can your item be treated? depends on if it has moving parts or not. If not, then yes. If so then possible depending on the components.

People get so concerned about this stuff but then they have two cups of GFO in their sump.

How old are the wet sides?

 

[JoshKReef]

People get so concerned about this stuff but then they have two cups of GFO in their sump.

How old are the wet sides?

Both were manufactured in February - March 2017, and touched water for the first time in March 2017.

 

[MarsRover]

The vinegar may remove the surface oxides, but unless it is an aesthetic (looks) concern only, I can't see how that eliminates other concerns, such as release of metals to the water.

+1 to what @Randy Holmes-Farley said.

I have been seeing this issue come up more and more lately, i hate the thought of rusting products. To be sure, even Al "rusts" but you don't see it, rather it's processes, if my memory serves me right, is to essentially dissolve into sea water.

I recall in materials class, or chemistry, somewhere in my undergrad, a textbook explaining that large ship hulls (made of steal) will have divers go under them and electrically connect/weld things like nickel to them, so that the seawater will selectively corrode that metal before eating the hull.

Also i remember in high school chemistry class using vinegar (i think...) to remove the surface protectant on some sort of steel wool product so that we could allow it to rust....

In the world of cheap overseas-made junk (and even cheap american junk for that matter) materials are not all created equal. I've seen this with even high end ScubaPro "titanium" dive knives actually showing your typical steel-red oxidation on it. But then I find a "lesser" Bear Grills model of a Gerber titanium knife while diving and the darn thing has never ever showed rust. It all depends on the alloy they use.

I'm curious to the OP and responders,@Josh Kraft @KMench, have you done triton testing? I'm curious if you have any heavy metals at any sort of elevated level?

I think it is pretty disingenuous, or maybe it truly is ignorance on the part of these product makers, to tell us it is merely an issue of ascetics. It also is a bummer when you spend hundreds on a "high end product" just to find it leaks a small amount of current into your system (my vortec L1 does this....certainly doesn't help any oxidation problems either...)

</rant>

 

[MarsRover]

My guess is some kind of stainless steel?

Yeah man, that definitely would appear to be some sort of steel alloy.

I'd challenge you to ask the company for what alloy (and manufacturer if you're really motivated) that shaft is made out of.

People get so concerned about this stuff but then they have two cups of GFO in their sump.

I always wondered about this. I am a non-GFO user myself. Curious though how with GFO you don't have any heavy metal issues? maybe @Randy Holmes-Farley can explain as i don't exactly know what GFO is chemically. There is something to be said though that in some cases, rust can have a shielding effect and protect the underlying metal from continuing to corrode. I forget exactly what cases oxidation shields and in other cases it continues to penetrate (like on your old school car for example....rust can eat straight through your steel fenders). One thing I think i recall (again, i'm a non-GFO user) isn't flow rate through your GFO reactor a big deal? Isn't it normally a very slow flow so that you don't get tumbling of the GFO for reasons of micro bits chipping off and contaminating the water?

interesting discussion....one day we will get to the bottom of this....maybe

 

[KMench]

@MarsRover I emailed them earlier this morning to ask what type of metal the impeller shaft was made from. We shall see what the response is ;Bored I’ve recently noticed the same problem and my MP40s are only about 8 months old. Got the same exact response email yesterday when I asked Vortech about the rust.

 

[Potatohead]

I'm not a metallurgist but I have to imagine using stainless steel in a submerged saltwater environment is nearly impossible to prevent rust, especially on a part that is constantly abraded. Typically you will see titanium or ceramic used in these scenarios (typically impeller shafts). I have some MP10's and the shafts in those are ceramic.

Now whether that small amount of rust is a big deal or not is another question, I personally doubt it and it most likely depends on overall water volume, etc.

 

[JoshKReef]

I'm not a metallurgist but I have to imagine using stainless steel in a submerged saltwater environment is nearly impossible to prevent rust, especially on a part that is constantly abraded. Typically you will see titanium or ceramic used in these scenarios (typically impeller shafts). I have some MP10's and the shafts in those are ceramic.

Now whether that small amount of rust is a big deal or not is another question, I personally doubt it and it most likely depends on overall water volume, etc.

Are they fully ceramic? Mine have a ceramic sleeve only.

 

[madweazl]

My MP40s (QD wets) have the same small amount of rust but nothing has shown up on three Triton tests. Hasnt concerned me too this point but thing I do wonder about is what the other end of the shaft is doing; is this part of the reason some of the magnets begin to rust and bust out of the housing?

 

[KJAG]

If it’s stainless it’s probably 304. I was under the impression that 316 stainless will not rust. I live at the beach and the marine environment destroys anything that isn’t copper or 316 stainless. I have two 316 deck handrails that have been up for years without a speck of rust, but the 304 in my neighborhood gets destroyed. From what I recall, even if 316 is submerged it won’t rust, but I could be mistaken. In response though, No, I don’t take that to be an acceptable answer from the manufacturer as there are materials that will not rust. Sounds like they didn’t do the research and/ or tried to cut corners.

 

[MarsRover]

I'm not a metallurgist but I have to imagine using stainless steel in a submerged saltwater environment is nearly impossible to prevent rust, especially on a part that is constantly abraded. Typically you will see titanium or ceramic used in these scenarios (typically impeller shafts). I have some MP10's and the shafts in those are ceramic. Now whether that small amount of rust is a big deal or not is another question, I personally doubt it and it most likely depends on overall water volume, etc.

I completely agree. All metal "rusts" also known as "tarnish" or "oxidizes" to one degree or another. The metal and the environment it lives in dictates the rate of oxidation and what the action is: i.e. accumulation of Iron oxide (like steel rusting where you actually have an additive effect on the bulk solid) or dissolving line in the case of Nickel and Aluminum in saltwater. This whole area of chemistry is called electrochemistry if anyone is interested in looking into it more. I believe the relative electron affinity of the metal and the environment (H2O vs NaCl + H2O) dictates what happens.... deposition or material loss..... could very well be wrong... don't quote me!


As an answer to the OP's question, and in light of what @Potatohead just said, the answer is "NO" i don't believe "it's just surface rust" is an acceptable answer. I would immediately have asked the person "well what affect to you expect iron oxidation to have on sensitive marine sessile invertebrates a closed system?" Not to mention all the other heavy metals they put in these alloys (i.e. chromium, Molybdenum, etc... in the case of stainless')

It may be a good answer from an engineering perspective relating to device failure, but not with respect to leaching of metals.

It's funny, this age-old scientist-engineer lack of concurrence is something i deal with regularly at work.... does the machine work? Heck yeah! Does it kill any life that may be there? Did it introduce contamination? (engineer stopped listening...) It's difficult because i was raised by scientists and consider myself both and frequently find myself having to communicate between the two types of brains!

My MP40s (QD wets) have the same small amount of rust but nothing has shown up on three Triton tests. Hasnt concerned me too this point but thing I do wonder about is what the other end of the shaft is doing; is this part of the reason some of the magnets begin to rust and bust out of the housing?

Do you run anything that could be absorbing the minor amounts of heavies? Chemipure, poly-filter, triton detox? Also, your tank says it's 75gal? and MP40's aren't that big right, so you probably only have a couple square inches of exposed metallic surface to water? My issue that brought me into this whole realm of discussion in multiple threads is my IceCap 3K gyre has two rather large magnets that were rusting and i had some bad heavy metals issues and couldn't figure out where it was coming from. Now that i sealed them with silicone, i am finally able to knock down the metals in the water not definitive...but possible cause?

If it’s stainless it’s probably 304. I was under the impression that 316 stainless will not rust. I live at the beach and the marine environment destroys anything that isn’t copper or 316 stainless. I have two 316 deck handrails that have been up for years without a speck of rust, but the 304 in my neighborhood gets destroyed. From what I recall, even if 316 is submerged it won’t rust, but I could be mistaken. In response though, No, I don’t take that to be an acceptable answer from the manufacturer as there are materials that will not rust. Sounds like they didn’t do the research and/ or tried to cut corners.

I'd bet those handrails aren't as shiny as they used to be! Pitting corrosion I believe is what one of the dissolving methods of oxidation is called when there is selective removal of surface metal from things that dissolve rather than "rust". You are probably right about what materials they are using though. Quick google search found this: https://www.bssa.org.uk/topics.php?article=100

 

[Daltrey]

As soon as I read the title I knew you were talking about vortech powerheads because I run them also. Just wait until the case holding the magnet splits and you realize it is full of rust also.

I'm looking to add two more and Ecotech's failure to do anything about this is seriously making me want to abandon ship. That and this piece of crap reeflink that has to be the worst piece of hardware/software I've ever had the misfortune to use.

 

[Potatohead]

Are they fully ceramic? Mine have a ceramic sleeve only.

All ceramic

I imagine in the MP40/60 the ceramic is too brittle to use entirely since the shaft is a lot larger, but I didn't design them so I can't be certain.