♪♪♪ (Jessica Russell) Hi, everyone.

My name is Jessica.

Welcome to Vegas PBS STEAM Camp.

"STEAM" stands for science, technology, engineering, arts and math.

And while it may sound like these are just subjects we learn in school, it's way more than that.

STEAM helps improve our lives and our community.

Today with the help of experts, we're going to learn about the STEAM that's all around us in Southern Nevada, which you might have never noticed before.

Then I'm going to show you fun activities you can do at home to learn more.

You'll even have a chance to send us videos or pictures of your results, but I'll talk about that a little more later.

To get started, we just need a question to investigate.

(ringing sound) Ah, hear that sound?

It means I'm getting a video call from my friend Andrea.

-Hey, Jessica.

-Hi, Andrea.

What question do you want to explore on today's show?

-I was wondering how aquariums work.

-That's a good one.

Let's ask my friend Ryan Ross, who's standing by at the Silverton aquarium to help us answer that question.

-My name is Ryan Ross.

I'm the aquarium curator here at the Silverton Casino Aquarium.

Now behind me, we have a 117,000 gallon saltwater tank.

We have about 2,000 individual animals and over 100 different species from all over the world, so it's a very unique collection of animals that you won't see anywhere else.

♪♪♪ Behind me is 117,000 gallons of saltwater.

Now, saltwater weighs just over eight pounds a gallon.

So if you do some quick math, these windows are holding back about one million pounds of water.

Any guesses on how thick these windows have to be to hold back one million pounds?

♪♪♪ The windows are six inches thick.

They're made of acrylic.

The maintenance that is required to maintain the window, we are constantly wiping down the windows of algae.

All the coral in there is artificial, so two days a week we spend all day underwater scrubbing, cleaning the coral and cleaning the gravel to help maintain the water clarity and make sure it's healthy for the animals.

So a very unique aspect of the aquarium is we have fish from all over the world.

Whether it's from the Caribbean or the Red Sea or the Indo-Pacific, we have fish from all over the world, and part of our job is to pick out animals we think have the right temperament and that are going to get along with everyone and to give you the collection that you see behind me.

So how do we maintain this aquarium?

How do we keep the water so clean and clear and healthy for the animals?

Well, we do that with a lot of different filtration methods.

We have sand filters, we have protein skimmers, we have ozone contact towers, 25-horsepower pumps moving the water through all those different types of filtration, and 117,000 gallons of water gets circulated about every 75 minutes.

The way we're able to create an ocean environment in the middle of the desert is we take a blend of the salts and all the trace elements you would find in natural seawater.

We add it to fresh water and essentially have ocean water here in the middle of the desert.

So the sand filters collect debris.

As they do that, filter pressures increase.

So two times a week we do a backwash, and we backwash 9,000 gallons of water through those sand filters.

Then we collect it in a basin in the ground and we clean that water up, and then we recycle it.

So the aquarium has been here 16 years, and we've only ever done one water change.

We're constantly recycling the water.

♪♪♪ Behind me is where our biological filtration takes place.

In these black towers is plastic sheeting from top to bottom, and what happens is the pumps move the water to the top of the black towers, and that water trickles down over that plastic sheeting.

Now, that plastic sheeting is surface area for bacteria to grow.

There's a lot of fish in the aquarium.

Fish go to the bathroom, and it creates ammonia which is toxic and will kill the fish.

So the bacteria that lives on that plastic sheeting converts the ammonia to less toxic things, allowing us to keep fish in captivity.

Behind me is another important part of our life-support system.

This is called a protein skimmer.

Now, how the protein skimmer works, proteins are very long skinny molecules.

They have a hydrophobic end and a hydrophilic end.

Now, the hydrophobic end, meaning phobia or scared of water, doesn't like water, is going to attach to a bubble and because they're long and skinny, a lot of proteins can attach to one of the millions of tiny little bubbles in there.

Those bubbles rise to the surface and collect all the proteins and organics to help keep the water clean and clear.

So this is the top of our aquarium.

This is where we come to get any water samples and to do any target feeding as well as to get in and do maintenance, whether that be cleaning the core or hand-feeding the stingrays.

So this is one of our handheld units that we use to keep the water parameters in check.

This measures dissolved oxygen levels, temperature and pH.

So the pH scale goes from zero to 14.

We like to keep our aquarium between 8.1 and 8.3.

Now, the closer you get to 14, the more basic you are, and the closer you get to zero, the more acidic you are.

So one of the problems you run into when you have an aquarium with 2,000 fish in it is you have some fish that are very aggressive feeders and some fish that are very shy feeders; some fish with big mouths, some fish with small mouths.

So what we've done is we've designed these nori feeders that allow us to stick seaweed in there, and it keeps it there for a while so they can't take it all at once and the aggressive fish don't swim off with everything, and it gives the more timid, the shy feeders an opportunity to get some nori.

Now, we also have bottom inhabitants like stingrays.

Stingrays are bottom feeders, and we actually have to get in.

Because of the 2,000 mouths to feed in here, we actually have to get in to hand-feed the stingrays.

If we would have to just throw the food on the surface, not enough of that food would make it to the bottom for the stingrays to eat.

I hope you found this look into an ocean habitat in the middle of the desert as fascinating as I do on a daily basis.

Next time you're at the Silverton, just remember everything that's going on behind the scenes, all the hard work to keep these animals happy and healthy.

♪♪♪ So I developed my interest in aquariums and marine biology at a very young age.

About seven years old, I bought my very first aquarium and it snowballed from there.

I knew I wanted to go to college for marine biology, and before I left for college, my bedroom was nothing but aquariums.

Unfortunately, my parents made me take all those aquariums down because they weren't going to take care of them while I was away at college.

But if you're ever interested in getting into the aquarium field or marine biology, I highly recommend volunteering at any local aquariums and definitely get a small aquarium and set it up at home.

I learned so much on my own at home taking care of fish as I did here on the job at a professional level.

You can learn a lot on your own by reading and just experimenting.

So I highly encourage it.

If the ocean interests you, if the aquarium world interests you, definitely go after it because it's a very rewarding and fun career.

Thanks, Ryan.

Let's review what we learned.

To create an ocean environment, aquariums add a special blend of salts and elements found in seawater to fresh water.

Aquariums keep the water healthy for the fish by pumping it through special filters that use sand, bacteria and even bubbles to clean and recycle the water.

Aquariums also keep the fish healthy by checking the water's pH level to make sure it's not too acidic or basic.

Aquarium staff feed the fish using special tools or by hand depending on the animal's size, personality and type of food they eat.

Thanks for taking us behind the scenes at the aquarium, Ryan.

I learned so much new information.

Now it's our turn to think like scientists.

Ryan says the water in the aquarium has to have the proper pH level to keep the fish healthy.

That makes me wonder if water has a pH level, do other liquids and substances have a pH level too?

To investigate, you will need to make some cabbage juice.

Cabbage juice is a natural pH indicator, which means you can use it to find out if a substance is an acid or a base.

All you have to do is mix a little bit of the liquid you want to test into the cabbage juice.

If the liquid has an acidic pH, the cabbage juice will turn pink or red.

And if the liquid you are testing has a more basic pH, the cabbage juice will turn blue or green.

Ask an adult to help you make the cabbage juice by cutting up a red cabbage and blending it with some warm water.

Using a strainer, help your adult strain the water out of the mixture into a bowl.

When you're done, it'll look purple like this.

Then gather the rest of your materials.

You'll need some clear cups, a marker, a label, a data collection chart and a variety of safe liquids to test.

Gather what you have on hand like vinegar, lemon juice, soda, milk, orange juice or even a sports drink.

You can even test baking soda or flour.

Before you get started, make a prediction.

Which substances will have an acidic pH and which will have a basic pH?

Once you prepare your materials, you're ready to investigate and collect data.

Label each cup with the substance you want to test and pour the same amount of cabbage juice into each one.

♪♪♪ Set one cup of the cabbage juice aside.

You can use this to see how much the color of your mixtures changed.

Then pour a little bit of your first substance into the cabbage juice, stir, and observe its color.

Record your observations on your data collection chart and repeat until you have tested all of your substances.

When you're finished, analyze your data.

You can even arrange the cups in order from most acidic, which will be the brightest pink, to the most basic, which will be the most bluish-green.

Were your predictions correct?

Which substances had an acidic pH and which had a basic pH?

And did the color of the water stay purple for any mixture?

If so, what does that mean?

Now let's check in with Ronaldo, who is doing this activity at home right now.

♪♪♪ (blender whirring) ♪♪♪ Me and my dad made some cabbage juice.

It smells really gross.

I am going to test some juice and soda, and I'm going to find out if it turns red, pink or blue.

My prediction is when I pour the juice in the cabbage juice, it's going to turn red because it kind of looks like red because it's super close to it.

♪♪♪ The juice made the cabbage juice turn kind of pinkish-reddish.

And the soda, I would say it will turn red or pink.

I noticed that when I poured the soda, it turned red but not so red.

It doesn't have as much acid as the juice does.

My prediction is that since white could turn any color, but I'm pretty sure it's more likely to become blue.

I noticed that it turned blue, so I would say it's a base.

Bye, Jessica!

-Thanks for sharing your investigation.

I can't wait to find out what the pH is of the other liquids you want to test.

An important part of being a scientist is sharing your work with others.

Visit our website at vegaspbs.org/steamcamp to submit videos or pictures of your pH investigation to us at Vegas PBS with your grown-up's permission, or ask your grown-up to share it with us on social media by tagging @vegaspbs.

Keep in mind if you're submitting a video, make sure we can see what you're doing and hear what you're saying.

Also, you want to keep your video to one minute or less.

We will post some of your investigations on our website, and if yours is selected, we will mail you this cool PBS Kids bag and a new book.

When you visit our website, you can also download the data collection chart for this investigation and explore PBS Kids shows and activities to learn more about aquariums and pH.

Speaking of learning more, one of the best ways to learn more about a topic is through a book.

Let's visit my friend Jennifer at the library.

She's going to share a clever book that helps us imagine what it's like to be a fish in an aquarium.

♪♪♪ (Jennifer Bell) Hi, everyone.

I'm Librarian Jennifer from the Summerlin Library, and I heard you just visited the aquarium.

Well, I thought what better way to celebrate than read the book Memoirs of a Goldfish by Devin Scillian.

Imagine you're a goldfish living in an aquarium until you get a roommate.

And then you get another roommate.

And another and another!

What would you do if you were a goldfish stuck with so many roommates?

Well, I guess you'll have to check out the book to find out.

I hope you come visit me at the library soon and check out Memoirs of a Goldfish by Devin Scillian.

Bye, everybody!

♪♪♪ Welcome back to Vegas PBS STEAM Camp.

I've already learned so much today, and I hope you have too.

Luckily we still have time left, so let's investigate another question.

(ringing sound) Sounds like another caller.

It's my friend Ronaldo.

-Hi, Jessica.

-Hi, Ronaldo.

Welcome to Vegas PBS STEAM Camp.

Do you have a question I can help answer on this half of the show?

-My question today is how do cranes work?

-That's a great question.

Tall buildings wouldn't be possible without cranes.

I have a friend named Kelly at Compass Equipment who is a crane expert and can help explain how they work.

Let's go talk to him.

-Hi.

My name is Kelly Hadland with Compass Equipment.

Have you ever wondered how tall buildings get built, and how they take all the little pieces from the ground and lift them up in the air?

Well, it couldn't be done without cranes just like this one.

Today we're going to learn how cranes work.

♪♪♪ What we see here is a luffing jib tower crane.

This crane is configured up about 120 feet tall right now to the part where the crane is swinging.

♪♪♪ The operator is up there in the cab taking signals from somebody.

"25 feet off the deck, slow it down, "looking good."

And you can see that the whole upper part of the machine is swinging and the lower part is fixed.

That's called the tower or the mast.

The part sticking up to the left at a 45-degree angle, that's called the jib.

That's what lifts all the loads up.

That holds everything in place.

Cranes use pulleys to help lift heavy loads with a lot less effort.

The reason pulleys make our lives a lot easier is that it cuts down on the force required to lift a load.

So to lift a load without a pulley, it requires full force of whatever weight you're picking.

But as you wrap the rope around a pulley system, the load is cut in half because now we're sharing the load between two different pieces.

Here we have a 55-pound weight, and if I try and lift it without a pulley, I have to lift up really hard to pick this.

Pulling 55 pounds takes a lot of force but if I use this pulley, it cuts the load in half.

Now I can easily just pull down with 25 pounds of force, half the weight, and it's much easier to lift.

Pulleys are used in more than just cranes.

Can you think of examples in your everyday life where you see pulleys in action?

Some real-world examples of pulleys in everyday life would include flagpoles, the blinds in your house, garage door openers and even elevators that take people up and down.

Let me show you how pulleys are used on a crane.

There's these pendants going up to the top of the jib that are using pulleys to cantilever all of the forces.

So if you look at the top of the jib in the upper left and you see these pinup bars coming down off to the right, you'll see these white pulleys up there and all those white pulleys have a wire rope going through them making mechanical advantage to be able to lift that jib up and down.

♪♪♪ Okay.

This is called the load block.

This is what picks everything up.

This does most of the work.

So anytime the customer wants to pick up a big heavy load, he'll hook up some rigging, which I'll show you in a minute, down on this hook and that's how we lift things up.

This big item, this big load block, it's heavy.

It weighs 2,600 pounds just by itself.

And you need that extra weight so that when the operator is moving the drum and the rope is coming off the drum, there's something pulling it down.

Otherwise the rope would just never make it to the ground.

It's also being held up by this wire rope.

So this steel rope is made up of a bunch of tiny little strands of wire, but all these little strands of wire are woven and woven on top of each other to get to a big diameter steel.

This rope is very strong.

There's no way we could break it.

This block right here can pick up on its own up to 55,000 pounds.

This wire rope comes down and it goes over this pulley right here, and then it goes up over pulleys on top of the crane.

And this pulley is also what's helping hold the load right here in place with this big shaft.

So I'll demonstrate how a load might be picked up.

Bill, if we can have him hoist up just a couple of feet, make the hook about eye level for me.

-All right.

Go ahead, just boom up and hold the load.

-You can see the wire rope and all these pieces right here are all just going to come up some.

Right now there's a big drum turning up on top of the crane that's winding rope onto the drum.

So it's just lifting it up.

It's not just me pushing with my finger.

That's good, Bill.

Thank you.

So this is called the hook, and you can see how big it is.

It's got this safety latch on it.

It can swivel freely on its own so if the load starts spinning, it doesn't spin the crane.

So when it's time for the riggers to put something on, they'll put a piece of rigging, and this could just go right here over the hook and then this could come down and hook onto something with some shackles.

Okay, so if this was picking a real load, this will start to come under extreme tension right now, and once it's fully tensioned, the operator is free to go fast.

Let's go ahead and go up-up as fast as we can.

Coming up!

♪♪♪ Well, that's all we have for today.

I hope you learned something about how cranes work.

Next time you're driving around and see either a tall building or a tall crane, you'll think back and remember how pulleys work and how cranes lift things up.

♪♪♪ When I was young, I was really interested in big heavy equipment, big dump trucks, big skid steer loaders, backhoes.

All the big dirt equipment you might see on a job site, I was very fascinated with those.

So I encourage you if you have a passion in learning how things are built or how things are made, get involved.

Go learn how to operate something or learn how to build something or how to repair something.

It's a lot of fun and a very good career to be a crane operator.

I highly encourage you to consider that, or to learn how to fix cranes is a very technical skill or learning how to design them and how big the steel or wire rope needs to be or how big the pulley needs to be.

It's a great industry and a lot of fun and very rewarding because you get to see big heavy equipment at work.

Thanks, Kelly.

Today we learned tall buildings wouldn't be possible without cranes.

Cranes use pulleys, which are wheels that hold a cable or rope.

Strong, thick steel cable is used on crane pulleys.

Pulleys allow the crane to lift heavy objects, called a load, by reducing the amount of force or effort needed.

The mast or tower of the crane gives it its height.

The jib is like the arm of the crane.

It moves up and down to lift the load.

To attach a load to a crane, it is hooked onto a heavy load block using cables called rigging.

Thanks for helping us learn how cranes use pulleys to lift heavy objects, Kelly.

Now it's our turn to think like engineers to build our own pulleys.

In order to do this, we are going to use the engineering design process.

All engineers start their work by coming up with a goal or a problem they want to solve.

Your goal is to build a pulley that can lift something heavy you find in your home.

Pick something you can still lift on your own, like a water jug.

Feel how heavy it is.

What materials do you have in your home you can use as a pulley to lift this object?

You will need something that has a thick cylinder shape, like a rolling pin or a broomstick, but those aren't the only things you can use.

Be creative and see what else you can find.

You will also need a rope.

After you've identified your materials, figure out what you will use to hold your pulley in place and draw a sketch of your design.

The next step is to create your pulley.

Take your time and test as you go.

This helps you save time and fix mistakes if you realize something isn't working.

After you've created your pulley, it's time to test it out.

Attach one end of your rope to your object and pull the other end.

Is it a lot easier to lift your object?

If so, awesome job.

But if you tested your pulley and it fell apart or it didn't make it easier to lift your object, it's okay.

Think about what you can do to improve your design and test it again.

Now let's check in with Abigail who is doing this activity at home right now.

-I'm using a broom.

I'm actually using two of my dining room chairs.

They have these circles in it that the broom can fit in.

Then I have this rope, but instead of tying it to a basket, I have it tied to a dumbbell.

I need to use something that rotates like this.

To be sure I'm going to secure it.

Okay.

♪♪♪ It works!

-Thanks for sharing your creative pulley, Abigail.

If you would like to send me a picture or video of your pulley, you can submit it through our website at vegaspbs.org/steamcamp with your grown-up's permission, or ask your grown-up to share it with us on social media by tagging @vegaspbs.

And remember if you're submitting a video, make sure we can see what you're doing and hear what you're saying.

Also, you want to keep your video to one minute or less.

We will select some projects for our website, and if we choose yours, you will get this cool PBS Kids bag and a new book.

When you visit our website, you'll also find the steps of the engineering design process that you will follow to build your pulley and links to PBS Kids shows and activities to learn more about pulleys and cranes.

Now I'm going to send it back to Jennifer at the library one more time who will share a book about a fictional construction crew of cats who use equipment like cranes to accomplish a goal.

♪♪♪ Hi, everyone.

Librarian Jennifer from the Summerlin Library, and I heard that today you learned all about cranes.

So I wanted to tell you about one of my favorite books featuring a construction company who uses cranes called Kitten Construction Company: A Bridge Too Fur.

It's no wonder that Marmalade, the best architect in Mewburg, is hired with her company, the House Kittens, to make Mewburg's newest bridge.

But what she didn't consider was that she'd have to work on a crane on a barge on the water.

Will their new construction project end up being dead in the water?

If you want to find out, check out Kitten Construction Company: A Bridge Too Fur by John Patrick Green from your local Las Vegas Clark County Library.

I hope I see you at the library soon.

♪♪♪