Over the years I have seen hundreds of thousands of dollars in damaged pump room equipment due to the improper storing of muriatic acid tanks/barrels within the pump room.
On average i would say 50% of the pump rooms I enter have the plug on the top of the acid barrel removed and the acid lines for pH control just going directly into the barrel; allowing acid fumes to escape into the pump room.
Now with that said many expensive pieces of equipment such as chlorine generator power supplies, UV power supplies and other expensive pieces of equipment have cooling fans (drawing the acid fumes into the equipment enclosures) and corrosion finds its way into these pieces of equipment. In some cases, just in a matter of weeks, signs of corrosion can appear.
You can dramatically increase the lifespan of your equipment and decrease the damage due to acid fumes by installing rubber bung plugs which are designed to seal the acid lines going into your acid tank and also by installing an acid scrubber which screws directly into the secondary plug on your acid tank.
The next time you are in your pump room, look to see if you have these precautions in place.