Sometimes rules get so simply stated they get taken too far. Here's some common sense.
1. Do NOT, never, never, never, use copper or brass anything on your tank. It IS poisonous, and salt water is hyperactive about dissolving metals.
2. The reason for not using metal hose clamps in salt water is common sense: they rust real fast and fail. It's also true that if a hose leaks underwater, it's rarely a big deal, so why hose clamp it at all? Just get a hose that nearly fits and use a hairdryer to make it slip on. If exterior---use the hair dryer. Ambient salt creep (splash) will make it rust.
3. If you have to use metal for something, pick stainless: razor-scrapers for salt water use are real resistent---not impervious, but resistent. Iron as a rule (and stainless steel is iron) is no huge deal in a tank if not excessive. GFO (granulated ferric oxide) that we use to absorb phosphate is oxidized iron granules. At worst---it might absorb some phosphate.
4. aluminum expanded and coated with ceramic is now being offered as a sort of reef rock, and might have some merit, but watch it with corals. Some people are reporting aluminum in the water. Aluminum does not dissolve readily in seawater but it will, slowly, so if you're going to use them you might run PolyFilter, which will absorb aluminum from water as a red stain, and bind it harmlessly.
5. Silver will corrode over long time, but generally your jewelry is safe. Gold is impervious.
6. Tin, zinc, etc, probably will dissolve: just don't leave them exposed.
In general, you are certainly ok to use a screwdriver or pliers or tongs or scissors or whatever in your tank in a brief action to fix something---but when you take them out, for the sake of the tool, rinse it in tapwater and dry it thoroughly to prevent rust. AND do not put a tool that has oil or gasoline or any chemical on it into your tank.
Brief exposure is not going to hurt stuff. A lost razor blade will just rust away over time: iron is not a big issue. Copper can hurt something, and oil, gasoline, contaminants or some big decorative metal item left in the tank are all no-no's. So are tv remotes and various sort of batteries, whether the ordinary sort or the fancier kind. Children for some reason have been known to cast their toy car or the tv remote into the tank. If this happens, run PolyFilter, run carbon, do a water change, and hope it wasn't in there too long.
1. Do NOT, never, never, never, use copper or brass anything on your tank. It IS poisonous, and salt water is hyperactive about dissolving metals.
2. The reason for not using metal hose clamps in salt water is common sense: they rust real fast and fail. It's also true that if a hose leaks underwater, it's rarely a big deal, so why hose clamp it at all? Just get a hose that nearly fits and use a hairdryer to make it slip on. If exterior---use the hair dryer. Ambient salt creep (splash) will make it rust.
3. If you have to use metal for something, pick stainless: razor-scrapers for salt water use are real resistent---not impervious, but resistent. Iron as a rule (and stainless steel is iron) is no huge deal in a tank if not excessive. GFO (granulated ferric oxide) that we use to absorb phosphate is oxidized iron granules. At worst---it might absorb some phosphate.
4. aluminum expanded and coated with ceramic is now being offered as a sort of reef rock, and might have some merit, but watch it with corals. Some people are reporting aluminum in the water. Aluminum does not dissolve readily in seawater but it will, slowly, so if you're going to use them you might run PolyFilter, which will absorb aluminum from water as a red stain, and bind it harmlessly.
5. Silver will corrode over long time, but generally your jewelry is safe. Gold is impervious.
6. Tin, zinc, etc, probably will dissolve: just don't leave them exposed.
In general, you are certainly ok to use a screwdriver or pliers or tongs or scissors or whatever in your tank in a brief action to fix something---but when you take them out, for the sake of the tool, rinse it in tapwater and dry it thoroughly to prevent rust. AND do not put a tool that has oil or gasoline or any chemical on it into your tank.
Brief exposure is not going to hurt stuff. A lost razor blade will just rust away over time: iron is not a big issue. Copper can hurt something, and oil, gasoline, contaminants or some big decorative metal item left in the tank are all no-no's. So are tv remotes and various sort of batteries, whether the ordinary sort or the fancier kind. Children for some reason have been known to cast their toy car or the tv remote into the tank. If this happens, run PolyFilter, run carbon, do a water change, and hope it wasn't in there too long.