Cooling off your tank water.

[Givmeanf]

I thought there was a discussion about cooling tank water on this site, maybe not.
Now there is, eh?
I don’t have the issue of cooling my tank water, yet. I came across this equipment while down another rabbit hole looking for something else and thought I needed to throw it out there before I forget.
I have no idea if this will work. My gut says yes. I would have to do some mechanical engineering math for myself to figure it out. You can too.
https://a.co/d/exMTCoW
Follow this link on Amazon, and you will find the photo below too.
It might be worth checking out.

 

[Givmeanf]

I know this equipment is really for computers, but ………..

 

[civics14]

I would be concerned with the components and rust more than anything. Not sure if something made for computers would be made to withstand saltwater

 

[Givmeanf]

The solid plate heat exchangers are aluminum.
Not sure about the other one, but if it is for computer components then it would be compatible with glycol.
And, I was acutely thinking of the plate heat exchanger submerged somewhere in the saltwater/system and the radiator/fan as air cooling the glycol in the closed loop. In-line pump circulation glycol. You could remote the radiator to under the tank or a window, closet, RA grill, etc

 

[chaples55]

The only metals you would want to put in a reef tank are 316 Stainless Steel (304 will rust, slowly) or titanium, with titanium being preferred. Aluminum is toxic.

High quality aquarium chillers use titanium heat exchangers. Titanium components can be hard to find and hard to work with for DIY purposes though. A place to look for 316 stainless steel components would be homebrewing equipment, for example a wort chiller. Another option would be a coil of marine grade brake line: https://a.co/d/hunUakx

 

[civics14]

wasn’t that the fear with some batches of marine pure years ago about it leaching aluminum wiping out peoples reef?

 

[Givmeanf]

This is the simple diagram. Add a bypass valve and a temperature sensor, not a thermostat and you could regulate the flow temperature. I would be more inclined to use the temperature sensor to slow the motor down, slowing the flow, rather than introduce another item of failure (a valve).

The only metals you would want to put in a reef tank are 316 Stainless Steel (304 will rust, slowly) or titanium, with titanium being preferred. Aluminum is toxic.

High quality aquarium chillers use titanium heat exchangers. Titanium components can be hard to find and hard to work with for DIY purposes though. A place to look for 316 stainless steel components would be homebrewing equipment, for example a wort chiller. Another option would be a coil of marine grade brake line: https://a.co/d/hunUakx

the article referenced above is not exactly on point. It is a study of instant saltwater and aluminum, but it does make reference to the possible adverse effect of Soluble aluminum and micro particles suspended In water are different than a block of aluminum.

The only metals you would want to put in a reef tank are 316 Stainless Steel (304 will rust, slowly) or titanium, with titanium being preferred. Aluminum is toxic.

High quality aquarium chillers use titanium heat exchangers. Titanium components can be hard to find and hard to work with for DIY purposes though. A place to look for 316 stainless steel components would be homebrewing equipment, for example a wort chiller. Another option would be a coil of marine grade brake line: https://a.co/d/hunUakx

The article you quote is not exactly on point. It is a study of soluble and micro particulates in instant reef water. But point taken. It does not infer that a block of aluminum is dangerous. But it could be.

 

[Givmeanf]

wasn’t that the fear with some batches of marine pure years ago about it leaching aluminum wiping out peoples reef?

That’s what Chaples55 referenced article is investigating. The aluminum content in instant reef water.

 

[Givmeanf]

After oxygen and silicon, aluminum is the third most abundant element in the Earth's crust (8.2%) and by far the most plentiful metal.
Imagine a vast landscape of rocks and minerals, with every 100 parts containing about 8 parts of aluminum.
Saltwater causes pitting on aluminum surfaces due to galvanic corrosion, which occurs when two dissimilar metals come into contact with each other (in this case, aluminum and salt).

Seems to be everywhere already.
I can’t believe I am now looking up this information!

And micro plastics seem to be a danger to coral reefs as well. Lots of plastic parts in an aquarium. PVC in particular! And that overseas company making your plastic parts are not worried about the quality of the plastic that they use or your corals.
And seems micro plastics are much more of a danger to the oceans than aluminum.
So whatcha gonna to do?

And to beat a dead horse ...............................................
How concerned are experts about these dangers?
What are the potential dangers of cooking with aluminum foil?
Perhaps surprisingly, experts aren’t overly concerned. “Studies show that while there is some leaching of aluminum from foil to food during the cooking process, the level is very low nothing the body cannot normally handle,” ........................
you likely aren’t cooking your food at temperatures high enough to have a significant impact on the amount of aluminum that is transferred.
When it comes to aluminum-foil toxicity, there is no difference between the shiny side and the dull side. (this one never crossed my mind.) No, the answer is no.

 

[chaples55]

That’s what Chaples55 referenced article is investigating. The aluminum content in instant reef water.

Marine Pure are porous ceramic filter media bricks. Ceramics do commonly contain aluminum oxides, but these bricks have been found to contain high amounts of it, and it does leech into the water over time. There are several documented cases of high aluminum concentration (confirmed with ICP tests) associated with coral mortality or stunting of growth. Example here. .457 ppm aluminum resulted in a tank crash.

The article I shared previously is by Randy Holmes-Farley, a well-respected chemist in our hobby. If you read further, he did a whole lot more than just investigate aluminum concentration in a salt mix. Among other things, he tested how much aluminum leeches from Phosguard, another filter media high in aluminum oxide. He found that dissolved aluminum levels increased to undesirable levels in just a couple weeks. Specifically, even after thorough rinsing of the media, aluminum rose to 0.25 ppm in just 2 weeks.

Saltwater causes pitting on aluminum surfaces due to galvanic corrosion

Yup, and that corrosion is aluminum oxide, which as seen above can quickly accumulate to harmful levels in a reef tank. You're welcome to try it, but it's really not worth the risk IMO, especially when there are suitable alternatives available.

aluminum is the third most abundant element in the Earth's crust

What really matters is the aluminum concentration in the ocean, which is only 0.013 to 5 ppb. There's a bunch of interesting research papers documenting the processes that keep this concentration so low, but those processes are not applicable in an aquarium environment.

I'll leave the discussion on micro plastics and food contact with aluminum for another day, since those aren't really relevant to the long-term safety and durability of aluminum in saltwater.

 

[Adam]

After oxygen and silicon, aluminum is the third most abundant element in the Earth's crust (8.2%) and by far the most plentiful metal.
Imagine a vast landscape of rocks and minerals, with every 100 parts containing about 8 parts of aluminum.
Saltwater causes pitting on aluminum surfaces due to galvanic corrosion, which occurs when two dissimilar metals come into contact with each other (in this case, aluminum and salt).

Seems to be everywhere already.
I can’t believe I am now looking up this information!

And micro plastics seem to be a danger to coral reefs as well. Lots of plastic parts in an aquarium. PVC in particular! And that overseas company making your plastic parts are not worried about the quality of the plastic that they use or your corals.
And seems micro plastics are much more of a danger to the oceans than aluminum.
So whatcha gonna to do?

And to beat a dead horse ...............................................
How concerned are experts about these dangers?
What are the potential dangers of cooking with aluminum foil?
Perhaps surprisingly, experts aren’t overly concerned. “Studies show that while there is some leaching of aluminum from foil to food during the cooking process, the level is very low nothing the body cannot normally handle,” ........................
you likely aren’t cooking your food at temperatures high enough to have a significant impact on the amount of aluminum that is transferred.
When it comes to aluminum-foil toxicity, there is no difference between the shiny side and the dull side. (this one never crossed my mind.) No, the answer is no.

There is a reason that chillers in this hobby use a refrigerant. It's simple BTU's.

Irregardless of the material used to make the thermal transfer block, the amount of energy and sheer size of the equipment needed at room temperature to achieve a 1°F drop in an aquarium would be far too cumbersome & expensive. You would be better off just taking a few cheap fans and directing them across the surface of the aquarium. Don't underestimate the effect of evaporative cooling.

 

[Givmeanf]

Marine Pure are porous ceramic filter media bricks. Ceramics do commonly contain aluminum oxides, but these bricks have been found to contain high amounts of it, and it does leech into the water over time. There are several documented cases of high aluminum concentration (confirmed with ICP tests) associated with coral mortality or stunting of growth. Example here. .457 ppm aluminum resulted in a tank crash.

The article I shared previously is by Randy Holmes-Farley, a well-respected chemist in our hobby. If you read further, he did a whole lot more than just investigate aluminum concentration in a salt mix. Among other things, he tested how much aluminum leeches from Phosguard, another filter media high in aluminum oxide. He found that dissolved aluminum levels increased to undesirable levels in just a couple weeks. Specifically, even after thorough rinsing of the media, aluminum rose to 0.25 ppm in just 2 weeks.


Yup, and that corrosion is aluminum oxide, which as seen above can quickly accumulate to harmful levels in a reef tank. You're welcome to try it, but it's really not worth the risk IMO, especially when there are suitable alternatives available.


What really matters is the aluminum concentration in the ocean, which is only 0.013 to 5 ppb. There's a bunch of interesting research papers documenting the processes that keep this concentration so low, but those processes are not applicable in an aquarium environment.

I'll leave the discussion on micro plastics and food contact with aluminum for another day, since those aren't really relevant to the long-term safety and durability of aluminum in saltwater.

Oh, believe me you have me reading ……..

 

[Givmeanf]

There is a reason that chillers in this hobby use a refrigerant. It's simple BTU's.

Irregardless of the material used to make the thermal transfer block, the amount of energy and sheer size of the equipment needed at room temperature to achieve a 1°F drop in an aquarium would be far too cumbersome & expensive. You would be better off just taking a few cheap fans and directing them across the surface of the aquarium. Don't underestimate the effect of evaporative cooling.

Ya I agree. And there are small chillers made for aquariums. And I’ll betcha someone figured this all out already and you just need to buy the right size, which can be a challenge as well! But easier. And money looks like you need some money.
I still might do the math just to put this to rest for myself.

 

[Adam]

Ya I agree. And there are small chillers made for aquariums. And I’ll betcha someone figured this all out already and you just need to buy the right size, which can be a challenge as well! But easier. And money looks like you need some money.
I still might do the math just to put this to rest for myself.

Just to try and break it down for you.

A cpu/gpu chiller is designed to cool, something like one square inch, from 50 to 60 Celsius to 35 to 40 Celsius. The normal ambient temp is 20-24C. That's quite a differential, for 1 square inch.

In a typical aquarium were trying to drop the volume of water from 27-28C to 25-26C. All with an ambient temp only a few degrees lower.
The only economical way to do that is with evaporation. I'd wager that a chiller would still cost less than a heat exchanger at room temp.

Evaporative cooler - Wikipedia

en.m.wikipedia.org