Tunze Magnet Issue

[Tron_954]

Good afternoon,

I thought the new magnets were saltwater safe, but is this normal? not sure if its rust or not, but have been experiencing issues a few weeks after adding this to my tank

Tunze Rust by J.L Photography, on Flickr

 

[rvitko]

The magnets themselves are ferrite, this is a ceramic material that is man made and can be magnetized, it cannot corrode, this is the same material almost all impeller magnets are made from. These magnets are mounted on an iron plate that is coated by polyurethane, the black filling you see around the magnets. One of two things is happening and just to put you at ease, nothing in these magnets is toxic, their is no nickel, zinc, rare earth elements, etc, just an iron plate, inert plastics and the ferrite magnets.

1) The magnet at some point picked up something magnetic that has rusted, this could be iron filings, steel wool, iron based phosphate removers (which are essentially rust) or even a staple or some other foreign object. This is the most common issue especially when the rust is widespread.

2) A small pinhole is present and sea water has reached the iron plate, this is rare but can happen, when this is the cause, the stain will have a focal point and some sort of visible bubble or hole in the polyurethane will be the source, it may be extremely small though. The stain will radiate out from this point and usually be fairly localized.

 

[Tron_954]

So there is an iron plate inside the ferrite...? and it is possibly leaking through crack or hole in the coating?

The polyurethane, isn't that like a plastic-ish coating that all other tunze equipment has on its magnets? if so, this one does not have it. Its exactly as is, in the picture.

 

[rvitko]

Look between the ferrite magnets, that black stuff is polyurethane, the iron plate is under the magnets and the polyurethane coats it. It is a stack, the plastic shell has an iron plate installed in the bottom, two magnets are stacked on it and the polyurethane is poured in but it is just to cover the iron, it is a few mm thick but not all the way to the top and over the magnets. Yes, when we use neodymium magnets, they are coated because they rust, ferrite does not rust and because it is weaker, we cannot coat it without a substantial loss of power.

 

[Tron_954]

Mine does not appear as you describe.

Im inspecting it with an LED light and it appears to be rusting even worse than at first glance. I don't see the coating as I've seen on other tunze products, even under the ferrite. It looks as if its just plastic from the actual powerhead bracket.

 

[Tron_954]

Is there a way for you to show me the magnet/bracket for the 6015 pump so I can compare to mine?

 

[rvitko]

This is an older 6015 magnet, the only difference is the shape of the ferrite magnets. The polyurethane is the black visible between the two magnets and around the edges, this is a liquid that is poured in and hardens, I am sure it is present on yours as well as the magnets would not stay in otherwise, they are just loose magnets on a loose iron plate and the poured poly is what seals the iron and holds everything in.

 

[Tron_954]

You mentioned there is a newer version to the bracket, I bought this from Amazon, through Tunze USA... Maybe there is a way I can get a new bracket, perhaps mine is faulty; or that. 0.1%

The pump works fine.

 

[rvitko]

What you have is the newest magnet and the standard bracket that comes with the 6015, they are two separate parts. Their is a new bracket but it is not standard on the 6015 which is an economy model, the silence clamp 6025.650 comes with all the other models, the basic 6025.510 comes with the 6015. I really think that this is only some iron based material that stuck to the magnet and stained it. Can you get a photo that is straight on and shows the full magnet from the back where the rust is? If you have ever used an iron based phosphate remover, I would be almost sure that that is what caused the stain and I think the brittle star living in the magnet speaks volumes about how this is not a toxicity issue.

 

[Tron_954]

I will post the photo tonight, I'm at work now. I do not use gfo or phosphate remover. Also, over the last 6 weeks, I've experienced excess algae growth and some coral is not looking as normal.

All this had coincided around the same time this issue started occurring. And while you mention it is not directly toxic, it has appeared to create a direct impact to the tank.


How do I either fix the issue or get a properly working magnet bracket. As of now, I'm not using the pump.

 

[rvitko]

If it is really the iron plate inside that is rusting, that is a warranty issue and we would send a new magnet half, but the majority of the time, all that has happened is the magnet picked up some iron particles.

 

[Tron_954]

Well other than taking the new photograph, can I disassemble that bracket with the ferrite to further inspect it?

 

[rvitko]

You can remove the clamp but that won't give us any more info, they don't break down further than that unless you destroy the magnet. The main way to check the cause is to clean it, you can soak it in CLR or dilute phosphoric acid for a few hours and rinse it very well and that will remove the staining, or while it is more labor intensive you can soak it in vinegar or citric acid and use a tooth brush and scotchbright pad. Coke (the soda) will also remove rust as it contains phosphoric acid, but it takes a long time, a few days. If you reinstall it after it is completely clean and free of any visible iron particles and it comes back, we would have to assume it is rusting from the inner iron plate.

 

[Tron_954]

Good morning Roger, here is that photo you requested. I took a toothpick to it to try and see how extreme it was... didn't do much!

20140808_112344 by J.L Photography, on Flickr