Aquarium Safe Metals
- Thread starter Maritimer
- Start date
Stainless is. Thinking not so much with aluminum. To my knowledge stainless is the only "safe" metal as it is self "sealed" with an oxygen barrier. All other metals bleed trace elements into the water. Any time I've seen metal objects or decorations placed in a tank they are always spray painted with a fish safe clear epoxy to avoid any contamination of the system they are being placed in.
Stainless like you stated does not oxidize , personally im using stainless still clamps going on 4yrs without any issues..
Btw the clamps aren't submerged, but if I had to use them fully submerged I would. Don't have experience with any epoxy, but quite sure the right type of epoxy would work.
Btw the clamps aren't submerged, but if I had to use them fully submerged I would. Don't have experience with any epoxy, but quite sure the right type of epoxy would work.
Not a yes or no answer as there are many different alloys of stainless steel. All can be oxidized in the presence of a strong enough oxidizer or condition. Even the more resistive alloys can leach ions into the water via electrolysis. Many things like band clamps are made from lower resistive grades of stainless steel in order to have higher properties elsewhere such as strength or flexibility. Many stainless clamps have non stainless worm screws too) Even in the 300 series there is a wide range from 301 "no way fresh or salt" to 316L which can resist most things including nuclear bombardment.
A better pick would be Titanium. Again there is more than one alloy of Ti. Ti is the only metal I use in fresh or salt. I use it for ground rods to strip errant electrical currents.
Aluminum oxidizes readily and quickly. Unlike steel oxide (rust) aluminum oxide is very hard and blocks Oxygen from getting past. Aluminum forms a thin protective layer of aluminum oxide. If worn away it will reform. you can force this protective layer to become thicker using electrical current. This is Anodizing.
A better pick would be Titanium. Again there is more than one alloy of Ti. Ti is the only metal I use in fresh or salt. I use it for ground rods to strip errant electrical currents.
Aluminum oxidizes readily and quickly. Unlike steel oxide (rust) aluminum oxide is very hard and blocks Oxygen from getting past. Aluminum forms a thin protective layer of aluminum oxide. If worn away it will reform. you can force this protective layer to become thicker using electrical current. This is Anodizing.
People make fish tanks of stainless steel and I've seen them but I'm not sure what is the minimum grade.
Aluminum is a no go AFAIK... even for top covers out of contact with water, they have been shown to poison fish - see here for more
http://www.planetcatfish.com/forum/viewtopic.php?t=33344
http://monsterfishkeepers.com/forums/threads/aluminum-ceramic-glass.660155/
Aluminum is a no go AFAIK... even for top covers out of contact with water, they have been shown to poison fish - see here for more
http://www.planetcatfish.com/forum/viewtopic.php?t=33344
http://monsterfishkeepers.com/forums/threads/aluminum-ceramic-glass.660155/
It goes without saying, that the main thing, that owners of fish tank care about is fish's health. If aquarium and it's contents are made from good materials, then fish's health will be at the nice level. So I have a rule, that it's better to use the organic decorations, that in addition can bring favor, like live rocks, instead of plastic ships, that are harmful for fish. You can read more at http://arcreef.com.
I've been doing a bit of research about this topic as well recently (due to replacing my anodized and painted aluminum lids on 2 Arowana tanks based on learning from some of Viktor's posts similar to above). Here are a few relevant points I've come across:
-- Aluminum: I've read on multiple sources that aluminum is actually quite stable (e.g. no oxidation) between PH of 4.0-8.0 -- though I've also seen figures of 7.0 and 8.5, so I'm really not sure what the upper limit is. As my water is about 8.0, I just don't want to take a chance with it (nor would I if it were 7.0). Anodization helps prevent oxidation, but it can get scratched, and anywhere it's cut, like on the ends will be exposed aluminum. As such, and as others have advised, imo best to avoid being around your tank.
-- Stainless Steel: While I've always thought of this as being aquarium safe, I'm not so super sure now. ViceGrip makes some good related points, and I also came across one guy on an aqua forum who claimed to be a metal engineer for a ship building company. As with everything take it with a grain of salt, but he stated it drove him crazy that nearly everyone considered SS in their tanks to be safe. His main point was that stainless steel doesn't meant it won't oxidize (rust), it just means it stains 'less' -- and when it does it's 5 times more toxic than other metals (except titanium). He didn't provide further data or advice to suggest how long this process would take, but my takeaway was it's something to consider and worthy of more research if you do have stainless steel in your tanks, esp. for some years.
-- Aluminum: I've read on multiple sources that aluminum is actually quite stable (e.g. no oxidation) between PH of 4.0-8.0 -- though I've also seen figures of 7.0 and 8.5, so I'm really not sure what the upper limit is. As my water is about 8.0, I just don't want to take a chance with it (nor would I if it were 7.0). Anodization helps prevent oxidation, but it can get scratched, and anywhere it's cut, like on the ends will be exposed aluminum. As such, and as others have advised, imo best to avoid being around your tank.
-- Stainless Steel: While I've always thought of this as being aquarium safe, I'm not so super sure now. ViceGrip makes some good related points, and I also came across one guy on an aqua forum who claimed to be a metal engineer for a ship building company. As with everything take it with a grain of salt, but he stated it drove him crazy that nearly everyone considered SS in their tanks to be safe. His main point was that stainless steel doesn't meant it won't oxidize (rust), it just means it stains 'less' -- and when it does it's 5 times more toxic than other metals (except titanium). He didn't provide further data or advice to suggest how long this process would take, but my takeaway was it's something to consider and worthy of more research if you do have stainless steel in your tanks, esp. for some years.
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dazzapolypterusweeksii
got a large tank, thousands of gallons IIRC, made of SS, just relatively recently.
I have a ss tank and used 316 grade you can use any grade ss for freshwater for marine i would only recommend 316 although 304 wouldnt cause any issues. I have made the mistake of using aluminum for an internal filter frame submerged and within 9 months it was shot and the angle used was 5mm thick it was so badly correded it gave way never again.i would apoxy anything aluminium if using submeerged but then cost comparison between the 2 ss is the better option with zero worry or maintenance