- [Narrator] What exactly is pool shock
and what does it mean to shock a pool?
Shocking is the process of adding a powerful
concentrated dose of chemicals, usually chlorine,
to your pool water.
This helps get rid of contaminants like algae
and helps revitalize your pool's regular sanitizer.
Shocking is really useful at the beginning of pool season
or after your pool's been heavily used.
And it can also be helpful to shock your pool once a week
as part of your regular pool maintenance routine.
But there are lots of types of shock on the market
and depending on the type of pool that you have
or the water problems you're dealing with,
some pool shocks are a waste of time and money.
So here's everything you need to know
about finding and using the right shock in your pool.
Let's dive in.
(upbeat music)
(water splashing)
Real quick, before we continue.
If you want more help taking care of your pool,
be sure to grab our free pool care
cheat sheet at swimuniversity.com/cheatsheet.
It's totally free and will help keep your pool
clean and clear all season long.
First, what does shock do to your pool water?
when you're shocking your pool,
you're adding enough chlorine
or oxidizer to refresh the sanitizer
and destroy the buildup of chloramines.
chloramines form when your regular chlorine
mixes with the nitrogen in things like sweat and body oil.
It's the byproduct of your chlorine that's done its job.
when chloramines are present,
it means your chlorine has been used up
and there's less available chlorine
or free chlorine to sanitize your water.
And less free chlorine means less sanitizer
keeping your water clean.
Adding shock to your pool raises your free chlorine levels
to the point where contaminants
like bacteria and algae are destroyed.
So what are the different types of pool shock?
Pool shock comes as either a super concentrated dose
of chlorine, AKA chlorine shock,
or as an oxidizer, AKA non-chlorine shock.
Chlorine-based pool shock is best
for treating algae and cloudy water
but it can affect your other water chemistry levels
like CYA and calcium hardness.
On the other hand, non-chlorine shock
isn't as harsh and is a great weekly treatment
for refreshing your free chlorine levels,
but it's not strong enough to tackle big algae issues.
Okay, so what's the best type of shock for your pool?
Not all pool shocks are right for every type of pool
or for every situation
and some will impact your other levels.
So before shocking your pool,
test and balance your pool water
and keep an eye on your pH, calcium hardness,
and CYA levels before and after adding shock to your pool.
Okay, here are three common pool shocks
and when to use them.
One cal-hypo shock.
Calcium hypochlorite shock or cal-hypo shock
is the most powerful form of chlorine shock out there
with the highest percentage of available chlorine.
Use cal-hypo shock if you have algae issues
or as a powerful weekly treatment
if you have problematic pool water.
Because it's such a high concentrated dose of chlorine,
you'll need to wait at least eight hours before swimming
and it's best to use cal-hypo shock at night.
This shock doesn't contain any cyanuric acid
which means it's unstabilized
and can be destroyed by the sun's UV rays.
Finally, be careful using cal-hypo shock
in saltwater pools since it contains calcium
and can cause scale buildup in a saltwater generator.
And cal-hypo might be too powerful for pools
on the smaller side, like Intex pools.
Two, dichlor shock.
sodium dichlor, AKA dichlor shock,
is another chlorine shock but it's less potent
than cal-hypo shock.
It's still an effective treatment for algae issues,
contaminant buildup, and weekly pool maintenance.
And because it contains sodium, it dissolves quickly
and can be used in all types of pools
including vinyl, plaster, painted and saltwater pools.
However, Dichlor shock is a stabilized shock
which means it contains cyanuric acid
so it will raise your CYA levels.
And that means you can add it to your pool during the day
since it's stabilized and protected
from the sun's UV rays,
but it can drastically increase your CYA levels.
Three, non-chlorine shock.
Non-chlorine shock works as an oxidizer
which means it helps revitalize your existing sanitizer.
However, it does not super sanitize your water
and kill contaminants on its own
so non-chlorine shock isn't effective
at tackling larger issues like algae.
On the other hand, since it doesn't contain harsh levels
of chlorine, this is a great shock
for weekly treatments or if you wanna swim
shortly after shocking your pool
and it won't affect your calcium or CYA level.
So what kind of shock should you use for algae?
If you've got algae or green water,
we recommend using cal-hypo shock.
This is the strongest version of chlorine shock
and can quickly kill contaminants
that have built up in the water.
Because non-chlorine shock isn't a sanitizer,
it won't eliminate a severe algae problem,
but depending on how bad the problem is,
a non-chlorine shock can help revitalize
your existing sanitizer enough
that it will do its job killing the algae spores.
What shock should I use in saltwater pools?
While cal-hypo shock is the most effective shock
for treating algae, it does contain calcium
and that calcium can build up in your water
over time causing scale buildup in your saltwater generator.
So if you have a saltwater pool,
use this type of shock sparingly
and monitor your calcium hardness levels,
or consider using dichlor shock
if you're okay with an increase in your CYA levels.
Now, what about the super chlorinate setting
on your saltwater generator?
While this adds more chlorine to your water,
it only raises free chlorine levels gradually
over a long period of time
so shock is best for quick effective treatments
to tackle algae and bacteria.
What kind of shock should I use for a smaller pool?
If you have a smaller aboveground pool,
traditional chlorine-based shocks
like cal-hypo might be too strong.
Because this shock is sold in doses for 10,000 gallons,
it may contain too much chlorine for smaller pools
and take too long to dissipate.
You may want to consider using liquid chlorine
like bleach to shock a smaller pool.
Household bleach can be powerful enough
to kill algae but it's easy to overdo it
so be sure to take things slowly.
Finally, when should I add pool shock?
We recommend shocking your pool once a week,
or at least every other week
to help maintain sanitized water.
And if you need help deciding when to add shock
to your pool, be sure to check out our other video
all about when to add shock.
And that's it, if you need more help
with pool maintenance, be sure to grab our free
pool care cheatsheet @swimuniversity.com/cheatsheet.
And if you found this video helpful, leave a comment,
hit the like button, and subscribe
for more pool maintenance tutorials throughout the season.
That's it, thanks again,
and happy swimming.