Not all plastic tanks are acid safe so check the codes for HDPEhttp://www3.sympatico.ca/n.rieck/docs/plastic_codes.HTML
Then TEST a small spot.
Better yet a hard scale or lime remover like CLR may work better and dissolve faster.
A strong Vinegar or a weak Sulphuric Acid solution would also be better than a HCL solution for fish.
Most fish are very pH sensitive so rinse very well...
Yes, muriatic acid can be used to clean old tubs. It is a strong acid that can help remove mineral deposits, soap scum, and grime from the surface of the tub. However, it is important to use it with caution as it can be harsh and may require proper ventilation and protective gear.
No
It will remove pigeon feces
I think it might remove rust AND pipes. Be careful with that stuff.
Muriatic acid, also known as hydrochloric acid, is often used in household cleaning to remove stains, rust, and mineral deposits. It is commonly used to clean concrete, brick, and metal surfaces, as well as to adjust pH levels in swimming pools. It is a highly corrosive substance and should be handled carefully with appropriate safety precautions.
Muriatic acid is used for cleaning toilet bowls and sinks because it is a strong acid that effectively breaks down hard water deposits, scale, and other stains. It can help remove mineral buildup and grime that are difficult to clean with regular cleaners. However, it is important to use it carefully as it is highly corrosive and can cause damage if not handled properly.
muriatic acid should work fairly well
Drain pool and clean with muriatic acid
You can remove mineral deposits from your teapot with a mild vinegar solution.
Use diluted muriatic acid and a scrub brush to remove efflorescence. Neutralize with water or ammonia.
When you hover your mouse over a specific item, there SHOULD be a small 'x' in the corner. Click it to remove said item from your aquarium. It then goes to your aquarium inventory (which can be acessed in the drop-down menu on the left side of the aquarium). ~Hope it helped~
Muriatic acid will remove concrete from marble. You can also sand it off. Using a scraper may also help to free it.