Cleaning up pond scum is a genuinely singular experience. It's gooey, slippery, made of broken-down organic materials, and, if left to its own devices, can choke the air out of your aquatic flora and fauna. On the other hand, the best pond cleaners make a thankless job neat and straightforward; they're transformative in terms of water clarity, quality, and algae control. Our best overall pond cleaner from Summit Responsible Solutions is a surprisingly simple fix—just a couple of bales of barley straw serve admirably as a natural pond water filter. Year-round control is as easy as using 1 bale per 1,000 gallons of water. I also included some chemical solutions and beneficial bacteria blends in both liquid and pellet form. Take a look below, and you'll find everything you need to keep your pond sparkling clean and crystal clear.
Summit Responsible Solutions clear-water barley straw bales
Staff pick
You'd never think that chucking a small bale of straw into your koi pond would work to clear up murky waters, but it does—you just need lots of patience.
Pros:
- Drop them in and wait—that's it
- 1,000 gallons per bale
- Natural filter
Cons:
- Can take weeks before you see any effect
- Doesn't affect moss on rocks
At first, it made no sense to me that you'd plop more organic material into a scummy, murky pond. But, it turns out that Summit's small barley straw bales are an incredibly effective filter and can clear the water in roughly 2 to 3 weeks. You simply drop a bale into your pond where there's the most water flow and bide your time. If the straw starts sinking, pull the bale out, let it dry for about a day, and then put it back in. Barley straw works as a clarifier because as it breaks down, it releases hydrogen peroxide. And the hydrogen peroxide is delivered in such low amounts, it won't hurt your fish or aquatic plants—but it will eradicate algal bloom.
BioSafe Systems GreenClean granular algaecide
Works on string and mat algae too
Treat up to 16,000 gallons of water per tub of BioSafe Systems' GreenClean algaecide.
Pros:
- Lasts forever if you have a small pond
- Chlorine, copper, and phosphate-free
- Works within 24 to 48 hours
Cons:
- Not cheap, but worth stocking up on
For swift, effective algae control, you can't beat GreenClean from BioSafe Systems. When used as directed, this oxygen-releasing blend is perfectly safe for all flora and fauna in your pond—except algae, of course. Within a couple of days, just a single GreenClean application can eradicate even the most stubborn string algae, neutralize foul odors, and wipe out mold and moss overgrowth. This 8-pound tub of cleaner will purify up to 16,000 gallons of water, so it's worth purchasing for peace of mind and an algae-free pond.
CrystalClear MuckOff pond sludge reducer
Thorough pond purification
These MuckOff tablets work via enzymatic breakdown and are great for digesting away stubborn goop in between rocks and gravel.
Pros:
- Safe for all aquatic life
- Treats 4,000 gallons for 4 months
- Even breaks down leaves and twigs
- 3-year shelf life
Cons:
- Can only be used in water above 50 degrees Fahrenheit
While you can buy MuckOff in various amounts, I'd recommend investing in this 96-tablet jar. For ponds around 4,000 gallons in capacity, it'll treat sludge for up to 4 months. You can rest assured that MuckOff's dosage is quite precise, as well. When used correctly, it's safe for the residents of your pond and produces 5 ppm (parts per million) of oxygen. Amazingly, MuckOff's pond cleaner tackles ammonia and nutrient accumulation, unlike some competitors. It is strong enough to digest fish waste, dead leaves, and small twigs. You'll want to refer to the dosage rate chart on the package to discover how many tablets your pond would need for monthly maintenance. For really dirty ponds, treat the water every 2 weeks until it begins to clear by evenly distributing the tablets.
Microbe Lift spring and summer pond cleaner
Pre-measured for easy application
After a long, cold season, the best thing you can do for your pond is to prep it with Microbe Lift.
Pros:
- Reduces accumulated organic waste
- Eight pre-measured packets
- Works faster than a filtration pump
- Clears muck in a couple days
Cons:
- Only comes with eight 2-ounce packets
Add a new tradition to your warm-season habits by using Microbe Lift's pond cleaner packets. Once the water temperature surpasses 50 degrees, it's time to drop in a packet of this water-soluble cellulase enzyme cleaner. Dead leaves and organic sediment are no match for this non-toxic, non-caustic cleaner blend, so it's perfect for use after cold months or whenever you find yourself with a pond full of sludge. Just one packet will speed up organic decomposition and put you well on the way to a crystal-clear pond.
Japanese trapdoor snails
Feasts on algae, muck, and leftover fish food
These may not be the sort of snails you'd serve with butter, garlic, and white wine—but they're hard-working, and hungry for the nasty goop mucking up your pond.
Pros:
- All-natural way to de-muck your pond
- Eats slime, fish food, and dead plants
- Reduces bottom waste
- Ten giant snails included
Cons:
- Need ten snails per 50 square feet, gets pricey
Imagine, if you will, a brigade of little vacuums that tidy up the bottom of your pond without a scrap of effort from you. It sounds fantastical, but it's not—meet the Japanese trapdoor pond snail, the snacker of slime, and feaster of fish food. The snails eat their way across mucky bottoms, leaving pristine water and rocks in their wake. Japanese trapdoor snails also live for 5 to 10 years when cared for correctly and cohabitate well with many types of pond fish. A word of advice—you may want to wait for temperate weather to order these chunky wee snails. Extreme temperatures during shipping, both cold and hot, can prove fatal to your muck-loving mollusk friends.
Bottom line
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As you can see, the best pond cleaners don't need to be chemical-laden doses of total devastation to garner results. Clumps of unassuming barley straw ended up winning our staff pick, and it makes complete sense. As the straw breaks down in the pond water, it releases small doses of hydrogen peroxide. With patience, you'll have a clear pond after 2 to 3 weeks that will stay clear as long as there's a bale of straw present at all times. It's a cheap, natural, and effective solution for even the muckiest ponds.
I have to say; I'm partial to those trapdoor snails though; they'd be an excellent gift for my mother-in-law, who has a big, beautiful goldfish pond with waterfalls. They're safe to add into your pond's ecosystem, and the inevitable snail population growth will keep the water crystal-clear without her lifting a finger.
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