Aluminum in reef ?

[PicoSavvy]

Is any form or alloy of aluminum reef safe? I was looking at a thermoelectric chiller and asked the seller, what material was the water block made of and he message me back telling me it was constructed out of aluminum, but in the listing it said it can be used in reef tank

[seabass]

I assume that the heat sink is aluminum, and not the part that goes in the water. Usually these require being plugged into an aquarium controller to regulate the cooling.

[PicoSavvy]

I assume the the heat sink is aluminum, and not the part that goes in the water. Usually these require being plugged into an aquarium controller to regulate the cooling.

No The model that I am talking about is not the iceprobe. It has a a water block like this

Where water goes circulates in it to cools

[jedimasterben]

Nope, that's not gonna work.

[PicoSavvy]

O, ok thanks. That is what I thought these Chinese company would lie about it being reef safe to make a sale. O and I provide the info you ask in the nanobox heat sink thread that you ask for

[evilc66]

Aluminum can be used in salt water, but it's the anodizing process that makes it work. It would have to be anodized to Mil Spec Type III, which is also known as hard anodizing. It's a much thicker oxide layer that protects the base metal. Adding a teflon sealer helps greatly too, but the effectiveness is only as good as the anodizer. If there are thin or missing spots (not hard to do due to how parts are hung during the anodizing process), then it introduces a point of failure.

 

The long and the short of it is that the prep work to make aluminum work in salt water isn't worth it, and it's not cheap. Grade 2 titanium would be a better choice for the water block, as that's what is used in commercial chillers.

[PicoSavvy]

True. I know aluminum can be anodized to protect it.(very doubtful thAt these Chinese companies do it though) I still don't know how the do it to a water block, like how do they anodize the inside completely. Good point about the titanium being saltwater safe, the hard part is finding someone that can mill or cnc titanium because not every shop can cut titanium

[SantaMonica]

Could always coat the interior of the block with epoxy and let it drain out.

[evilc66]

True. I know aluminum can be anodized to protect it.(very doubtful thAt these Chinese companies do it though) I still don't know how the do it to a water block, like how do they anodize the inside completely. Good point about the titanium being saltwater safe, the hard part is finding someone that can mill or cnc titanium because not every shop can cut titanium

You are right, there is a very slim chance that these cheap water blocks are anodized beyond the most basic level. But anodizing is not just applied to an exterior surface. Anodizing is where you place an aluminum object into sulfuric acid and pass a current through the whole setup. The anode will be a conductive wire used to hang the part, and the cathode will be in the sulfuric acid. Anywhere the sulfuric acid touches will for the oxide layer. It's the point where the anode touches the part where the oxide layer is the thinnest, and is the problem area. Anodizing the interior of a water block like that isn't an issue.

 

Could always coat the interior of the block with epoxy and let it drain out.

There is always that, but with a block this small, any impedance to thermal transfer will drastically reduce it's effectiveness.

[PicoSavvy]

You are right, there is a very slim chance that these cheap water blocks are anodized beyond the most basic level. But anodizing is not just applied to an exterior surface. Anodizing is where you place an aluminum object into sulfuric acid and pass a current through the whole setup. The anode will be a conductive wire used to hang the part, and the cathode will be in the sulfuric acid. Anywhere the sulfuric acid touches will for the oxide layer. It's the point where the anode touches the part where the oxide layer is the thinnest, and is the problem area. Anodizing the interior of a water block like that isn't an issue.

 

 

There is always that, but with a block this small, any impedance to thermal transfer will drastically reduce it's effectiveness.

Hey evilc66 do you a link where I an find more information on that process. Is it just a sulfuric acid container with electricity running through it

[evilc66]

Just do a search for DIY anodizing. There should be tons of different articles and links to providers of materials and equipment.