Is your showerhead blocked by unsightly calcium deposits? Hard water, particularly from wells, can be high in calcium, magnesium, lime, silica and other minerals. Once hard water passing through a showerhead dries, it leaves behind deposits. This mineral buildup is both unattractive and problematic, as it can plug up the waterways, and prevent your showerhead from flowing at full blast.
Removing the shower head to clean it is by far the most effective method, and is relatively easy. However, it is important that you use caution and monitor the process closely if you have a shower head with a designer finish like oil rubbed bronze, brushed nickel, or antique copper. Chrome will stand up to straight table vinegar with no problems, but if you have any other finish we recommend taking a cotton swab and testing a small, inconspicuous area for up to 30 minutes before you use this method on your whole shower head.
If you are having stubborn stain issues, you can soak the shower head even longer to see if it will blast away.  If you wish, you can use some baking soda and rub that in to the small nozzles with a cleaning toothbrush which will help break down any additional limescale and remove the discolouration.  Rinse it clean and you should notice a difference.  Keep in mind that brown discolouration is ugly (I believe this has to do with iron content in water), but is not harming the functionality of the shower head. Green and white ‘crust’ is what you really need to work on, calcium and limescale are the culprits in clogging your shower head.
Never mind my earlier question. I should’ve watched the video BEFORE I submitted my question. The video answered my question. It’s much simpler than I was thinking. I was trying to avoid having to detach the hose from the spout coming out of the wall. But after watching that video, I see that that’s not necessary, that I can just let it soak in vinegar in the bag while it hangs on its hook. So please disregard my earlier question. Once again, thanks for the handy dandy tip!!
Step 1—scrubbing the shower head nozzles with a toothbrush—may not manage to remove all mineral deposits. That’s OK: You can clean off the remainder with household vinegar, whose mild acidity actually dissolves the deposits. To do this, fill a plastic bag with vinegar, then fit the bag over the shower head so that the nozzles are completely submerged. Secure the bag with a zip tie or binder clip, leaving it in place for several hours or overnight. Remember to run the shower for a minute before jumping in to bathe—you don’t want to end up smelling like salad dressing, do you?
These days many shower heads are made from flexible rubber. This means, you are saved from removing the shower head as well. Then how do you do it? You can just use your fingers and massage the nozzles to eliminate the clogging. Alternatively, you may use a toothbrush to clean the nozzles too. In basic terms, what this means is that you can solely use fingers or a toothbrush to realize your objective.
Although it's very safe to use, you will want to take some precautions when using vinegar as a cleaner. First, be sure to avoid contact with the eyes. If any vinegar gets in your eyes, promptly rinse the entire eye with fresh water, until the sting has completely dissipated. Also, note that while it's safe to use vinegar to clean areas where children play, it's best to do so when they aren't present. Like adults, children shouldn't consume large amounts of vinegar, so be sure to store it out of their reach.
About 14 months ago, I needed to clean the shower before company arrived, but had just taken a shower. I sprayed the wet shower with lemon juice and noticed when repeating the spraying that it seemed to be working faster than it had when starting with a dry shower. Since then, I’ve been spraying the shower after using it (while still wet) with a light spray of lemon juice. I have not needed to scrub the shower since! All that’s needed is wiping it with a cloth dipped in warm water, and occasionally, a little Soft Scrub when I feel a rough patch where soap scum is starting to build up. This method has also removed the previously nearly impossible to remove stains on the flexible hose and fittings to the shower head and the shower curtain liner.
As we're sure you're aware, many common household cleaners contain harsh chemicals that are toxic when in contact with your skin or eyes, and your lungs when sprayed into the air. Using such chemicals can cause allergic reactions for some, but there's good news! Many of these chemical cleaners can be replaced with common kitchen items, like vinegar. Vinegar is safe for you and your family, and when used properly can be a powerful tool in your cleaning arsenal. In addition, vinegar is very inexpensive when compared to household cleaners. You can find a gallon of vinegar at the grocery store for a fraction of the price of one small bottle of chemical cleaner.
There are many reasons to make cleaning with vinegar a regular part of your housekeeping routine. First, it's inexpensive, virtually pennies for each cleaning. You'll save several dollars by not purchasing unnecessary specialty cleaners. And given that it's all natural, there are no harsh chemicals or fumes to worry about. You can even use it to clean children's bedrooms and bathrooms with no additional concerns. 

clean shower head of limescale