Pond materials question:

[Marshall]

Does anyone know if stainless steel is okay to use in a pond water system ? it will be the reservoir tank for UV sterilizer which means it will be in contact with the water a little but not actually in the pond itself...

 

[Meyer Jordan]

Stainless steel is perfectly safe for use in ponds.

 

[Marshall]

Stainless steel is perfectly safe for use in ponds.

Okay cool. Thanks. I was worried I had done all that welding and material cost for nothing lol. Stainless is expensive especially the welding wire which literally costs about 10 times as much as the flux-core for carbon steel. Not to mention it is much more complex to weld.

 

[Meyer Jordan]

Next to Titanium, SS is probably the safest material to use.

 

[Marshall]

Next to Titanium, SS is probably the safest material to use.

What about aluminum ?

 

[Smaug]

Most aluminum will corrode if left in water.

 

[Marshall]

Most aluminum will corrode if left in water.

I have used untreated aluminum in holding tanks for water that cools the table for my plasma cutter and it holds up really well after it gets a thin oxide coating but the real issue I was concerned about with any metals in the pond is more about their toxicity and/or hepatotoxin by products to the fish.

 

[Marshall]

I would love to be able to have a custom glass lining in the tanks as that is probably the most stable surface material but obviously it would have to kept from breaking and would be expensive if not impossible to have custom made for the unusual shape and dimensions of the boxes I custom weld.

 

[Smaug]

Anything that oxidizes is going to leach something into the water. Even ss isn't immune from oxidation it's just a question of what is it that's being released into the water.

 

[Meyer Jordan]

Aluminum can be toxic to aquatic organisms. Toxicity increases at lower pH levels (<6.0). Like all other metals, aluminum is a bio-accumulate and its health effects may not manifest for some period of time.
Stainless steel may also oxidize, but Iron is the least toxic of all of the metals.

 

[Marshall]

Aluminum can be toxic to aquatic organisms. Toxicity increases at lower pH levels (<6.0). Like all other metals, aluminum is a bio-accumulate and its health effects may not manifest for some period of time.
Stainless steel may also oxidize, but Iron is the least toxic of all of the metals.

Aluminum is also frequently alloyed and not always advertised as such. Often containing beryllium which is extremely toxic even to humans, sometimes acutely and after only brief exposure.

 

[crsublette]

http://cdn.intechopen.com/pdfs-wm/33625.pdf

If using stainless steel, then I would also be careful about allowing chloride reaching too high or (if necessary) do small doses over a period of time...

Although, depending on your stainless steel grade, can take a large amount of chloride to have an impact on the stainless steel and the fish would be constantly changing these chloride levels, but, still should be something to think about when deciding how much chloride to use to treat the fish as a preventative against significant nitrite accumulation.... easy fix, build a water system that does not allow nitrites to accumulate in the first place...

 

[Meyer Jordan]

http://cdn.intechopen.com/pdfs-wm/33625.pdf

If using stainless steel, then I would also be careful about allowing chloride reaching too high or (if necessary) do small doses over a period of time...

Although, depending on your stainless steel grade, can take a large amount of chloride to have an impact on the stainless steel and the fish would be constantly changing these chloride levels, but, still should be something to think about when deciding how much chloride to use to treat the fish as a preventative against significant nitrite accumulation.... easy fix, build a water system that does not allow nitrites to accumulate in the first place...

As with too many quasi-research papers, elemental levels are only offered in very general terms....High/Low. As a result, not much can truly be derived from documents such as these. Specific levels should be defined and delineated before any rational judgement can be made concerning cause and effect. In this case, at what level does chloride begin to affect stainless steel. I would venture to state that in a well designed and functioning garden pond, there would never be a reason to elevate chloride content to a level.where the integrity of stainless steel would be greatly affected.

 

[crsublette]

As with too many quasi-research papers, elemental levels are only offered in very general terms....High/Low.

...that seems a little harsh.... I imagine they actually did do the tests...

My point in hyperlinking this was to indicate care should be taken when considering dosing high level of a chloride... that is all...

As a result, not much can truly be derived from documents such as these. Specific levels should be defined and delineated before any rational judgement can be made concerning cause and effect. In this case, at what level does chloride begin to affect stainless steel.

I agree... to which specific levels can be easily found elsewhere.

For those sincerely curious or concerned about this, simply do a google for "chloride ppm corrode corrosion stainless steel" and include the grade of stainless steel.

I doubt these levels would be reached... unless purposely dosing to prevent nitrite poisoning, which the going ratio among the koi hobbyists is around 7:1 to 10:1 (chloride to nitrite)... in other aquaculture operations, I often read anywhere from 10:1 to 20:1 (chloride to nitrite), which this discrepancy is likely dependent on the fish species.

I would venture to state that in a well designed and functioning garden pond, there would never be a reason to elevate chloride content to a level.where the integrity of stainless steel would be greatly affected.

Absolutely 100% agree.

 

[Marshall]

http://cdn.intechopen.com/pdfs-wm/33625.pdf

If using stainless steel, then I would also be careful about allowing chloride reaching too high or (if necessary) do small doses over a period of time...

Although, depending on your stainless steel grade, can take a large amount of chloride to have an impact on the stainless steel and the fish would be constantly changing these chloride levels, but, still should be something to think about when deciding how much chloride to use to treat the fish as a preventative against significant nitrite accumulation.... easy fix, build a water system that does not allow nitrites to accumulate in the first place...

I have well-water and some serious filtering so no chloride but the grade of stainless I use is intended for use in aileron and elevator repairs so it is designed to survive some pretty crazy environments including going from 70 F to -25 F in about 4 minutes