Love My Nugget Ice Maker, Hate Cleaning the Mold and Slime: Here Are My Weird Tips

I love my GE Profile Opal 2.0 ice maker. The nugget ice it makes is so much more crunchable than cubes. We use it to fill my teen daughter’s water bottle, to serve up fizzy, bubbly soda and for icy lemonade. We’re a healthier and more hydrated household since we bought this ice machine.

But it wasn’t cheap. Although my exact model has been phased out, it cost about $600, including a side water tank, when I bought it in 2024. I could practically fly round-trip to London for that.

And the Opal 2.0 has issues. Because water sits in it all the time, all of a sudden, it gets gross. Sometimes I start scooping out ice for a drink and see black debris on the nugget ice. Other times, I catch a glimpse of the side water tank and spot a green tinge, like algae is forming inside the reservoir. It’s embarrassing and disgusting, especially if I have guests over.

Why does my ice maker get dirty?

After two years of not knowing what was going on in my ice maker, I went straight to the source.

“The green film is likely algae growth, and happens if water has been left standing in the tank for an extended period and the tank is exposed to sunlight,” said Libby Lewis, product marketing senior manager at GE Appliances. The black debris, meanwhile, “is typically deposits from hard water.”

Knowing what the green and black gunk is doesn’t make me feel a lot better. The green tinge settles inside the water tank where a brush can’t reach, and both it and the black residue on the cubes come and go with no real pattern. 

One day the ice is fine, and I don’t even think about cleaning the machine, and then the next day I have to apologize to my book club and steer them away from using ice. Sorry, suddenly my ice looks like witches’ teeth! Hope you like warm cocktails, everybody!

How do I clean my GE nugget ice maker?

Over my two years of ice-machine ownership, I’ve developed a cleaning system that really works for me. It takes time, and you’ll need to use some unusual tools that you won’t see mentioned in the instruction manual. But it’s 100% worth it. Right now, my ice machine gleams, and the ice comes out as clear as glass. Here’s how to do it.

Tip 1: Only use filtered water

This one might seem obvious, but I admit, I’ve been lazy in the past and just filled the reservoir tank from my tap. No more. I’m lucky enough to have a filtered water faucet built into my sink, and even though it takes longer to fill the tank, I force myself to use it every time. 

If you don’t have a filtered faucet, maybe you have a Brita or other filtered pitcher. Use water from that. It helps keep the ice maker clean longer.

Tip 2: Rice, rice, baby

Spotting a green tinge that could only be algae in my side water tank horrified me. The green sheen was visible through the clear corners on the top of the tank, and it was honestly disgusting. 

I tried reaching the green algae first with paper towels, then with paper towels pushed in with chopsticks, and then with tiny, bendable baby-bottle brushes. I filled it with hot water and a little soap to try to dissolve the green color. It made some difference. But part of the green sat safely out of reach, and the tank didn’t come apart for easier scrubbing.

Nothing worked until I spotted this tip somewhere online. This is weird advice, but trust me, it works: Fill the side water tank with a cup of uncooked rice and soapy water (I didn’t use filtered here), then shake it. That method cleans out the corners that nothing else can reach. 

Remove the tank from its base, then pour in about a cup or less of uncooked white rice. Fill the tank halfway with water, add a squirt of dish soap and shake the container like you’re Tom Cruise bartending in the movie Cocktail.

The results are amazing – you can actually see the green smudges slipping away while you shake. After the tank is clean, I dump the soapy, dirty rice water, then rinse repeatedly with clear, clean water. (No one wants to taste soap or rice residue in their nugget ice.) 

You can try this with just soap and water, but I feel like the rice grains dig into the dirty corners in a way that soapy water alone doesn’t. And now I clean the reservoir tank every week or so, even when it’s still clear, just to get ahead of the algae problem. (Once I ran it through the dishwasher, but the manual warns against this. I can see why, as it could melt or buckle in the dishwasher’s heat.)

“Our cleaning standard for the tank has been to use warm soapy water to clean with some sort of bottle brush,” said Lewis of GE. “We have not heard of the rice technique, and that is interesting.”

Lewis also said there’s a reason the side tank doesn’t come apart, which would certainly make cleaning a cinch. The ice maker uses a gravity-fed system, which means it moves water from a higher location to a lower one using only the natural pull of gravity.

“If there were any air gaps, the gravity system would not be able to achieve equilibrium, and the product would overflow,” she said.

Tip 3: Buy a long aquarium brush

I was also bothered by the ice maker’s dirty tubing. My Opal 2.0 has two thin plastic tubes in the back. One connects to the reservoir tank, and the other to the back of the machine. After a while, they get dirty, which is visible from the outside. The tubes can’t be removed; they can only be unhooked from one end, so you can’t run water all the way through them to rinse them.

“The two tubes tend to fill with mineral scale as water sits in them,” Lewis told me. “It’s best to lay the plugged tubes flat during regular descaling to ensure the descaling agent can get to the tube surfaces and dissolve any mineral deposits. Using a long brush is also a reasonable solution. These tubes cannot currently be detached easily – it would require taking the Opal apart.”

I tried cleaning them with a thin baby-bottle brush to no avail – it just didn’t go far enough into the tubes.

But I found a solution. I ended up buying a long, flexible brush meant for cleaning aquarium filter tubing from pet-supply site Chewy.com. (Similar brushes are used to clean feeding tubes for medical purposes – those will also work.)

Now, finally, I had a brush attached to a long enough wire to push through the tubes and clean them.

But then, another snag. I reached a point where the aquarium brush simply stopped letting me feed it into the water tube and would not go any further. My co-worker Jeff Carlson, who was with me photographing the cleaning process, came up with a brilliant suggestion: Squirt dish soap onto the aquarium brush so it would slide more easily through the tubing. It worked, and the brush cleaned the tubing entirely. Then rinse the tubing to wash out the soap.

Tip 4: Wash out the ice bin

The tubing and the water reservoir tank are the most difficult parts of the ice maker to clean, but the other parts matter, too. I’m horrified when, upon occasion, I scoop some ice out of the bin and discover it’s dotted with black debris. Turns out, those are the hard-water deposits Lewis mentioned.

“Using the scale-inhibiting filter would help reduce buildup in the machine,” Lewis said, “but it is dependent on the area you live and the hardness of your water.”

Scale-inhibiting filter? There’s a filter? Back when I bought my Opal 2.0 in the summer of 2024, these were not yet available, but now Lewis says they are shipped with the ice maker. Those of us with older machines can buy one and use it, but it must be replaced every three months.

I’m planning to order a filter, but for now, I needed to use some elbow grease. I removed the ice bin, emptied it, and scrubbed it down in the sink with soap, water and a clean rag. I scooped as much water as possible out of the area under the ice bin and soaked up the rest with cloths. 

Then, I opened a new disposable toothbrush and scrubbed. It worked, and the bin became so clean I could eat out of it – which is essentially what I do every time I scoop ice.

Tip 5: Use vinegar to clean and descale

The owner’s manual recommends cleaning and descaling your ice maker every two to three weeks. “Descaling” means to remove hard, crusty mineral buildup, like calcium and lime, left behind by evaporating water. 

The manual notes that if you only use distilled water, you don’t have to do this as often. I use filtered water, but it’s not distilled. There’s a big difference: While filtered water passes through physical or carbon barriers that trap chlorine, heavy metals and debris, it keeps beneficial minerals like calcium, magnesium and potassium. Distilled water is boiled into steam and cooled back into liquid in a separate container, leaving everything behind. I’m going to keep on using filtered water, even if it means I have to descale more often.

Descaling is tricky because you may not really see a reason to do so. But it’s also easy. The online instructions are clear – unplug and drain the machine, then fill the reservoir with hot vinegar and run up to three cleaning cycles. Eventually, run three more rinse cycles using fresh water.

Tip 6: Sanitize with bleach

While you do use vinegar to descale, you use bleach to sanitize – don’t ever, ever mix the two! Mixing bleach and vinegar creates toxic chlorine gas.

But you can use bleach to sanitize your ice maker. Follow the instructions in the online or paper manual for your model. Essentially, you unplug the machine and drain it. Create a mixture of 5 cups of hot water and just 1 teaspoon of bleach. Pour that into the water reservoir and use the cleaning cycle. (It only takes three minutes.) Drain the machine as per the instructions and run fresh water through it multiple times to remove every last bit of bleach.

I know only too well that this sounds like a lot of work. I can’t pretend it’s simple. But for me, it’s absolutely worth it. My nugget ice maker is the best appliance I own, and I’ll willingly take on a bit of work to get it back in business. Cheers!

CNET editor Gael Fashingbauer Cooper, a journalist and pop-culture junkie, is co-author of “Whatever Happened to Pudding Pops? The Lost Toys, Tastes and Trends of the ’70s and ’80s,” as well as “The Totally Sweet ’90s.” She’s been a journalist since 1989, working at Mpls.St.Paul Magazine, Twin Cities Sidewalk, the Minneapolis Star Tribune, and NBC News Digital. She’s Gen X in birthdate, word and deed. If Marathon candy bars ever come back, she’ll be first in line.

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