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Availability:
In Stock.
Arrives
Sunday, Oct 11
Size: 4-Ounce
Style: Freshwater
Features
- Contains one (1) API ALGAEFIX Algae Control 4-Ounce Bottle
- Controls algae growth and keeps aquarium glass, ornaments and plants clean
- Fast-acting and effective on "green water" algae blooms, string or hair algae
- Will not harm fish and plants when used as directed
- Dose every three days until algae is under control then dose weekly
Description
Treat and control algae growth and reduce your freshwater aquarium maintenance with API ALGAEFIX Algae Control. This revolutionary product is specially developed to control many types of algae, including "green water" algal blooms and string or hair algae, and it will not harm fish or plants when used as directed. Weekly doses of API ALGAEFIX Algae Control will control algae growth and reduce aquarium maintenance. Do not overdose. To treat algae, add 1 ml per 10 gallons of water and repeat every three days until algae is controlled. Siphon or scrape any dead algae from aquarium. Use this aquarium treatment weekly to control algae growth and reduce aquarium maintenance. API ALGAEFIX Algae Control is not for use with freshwater crustaceans including shrimp, crabs and lobsters. With API aquarium products, it’s easy to keep a beautiful saltwater, freshwater or reef aquarium. For almost 60 years API has developed premium solutions with proven and effective results for your family and ours. API offers a range of testing kits, water conditioners, and nutritionally superior food, because we’re dedicated to making a better underwater world. They work to provide a safe, hospitable environment for fish such as tropical community fish, cichlids, goldfish and more. At API, we understand the rewards and relaxation of fishkeeping because we have a passion for fish too.
Brand: API
Liquid Volume: 4 fluid ounces
Item Weight: 2.4 ounces
Item Form: Liquid
Number of Packs: 1
Product Dimensions : 1.63 x 1.63 x 5.25 inches; 2.4 ounces
Item model number : 87C
Department : Unisex-Adult
Date First Available : June 20, 2004
Manufacturer : Mars Fishcare
Best Sellers Rank: #2,600 in Pet Supplies (See Top 100 in Pet Supplies) #7 in Aquarium Water Treatments
#7 in Aquarium Water Treatments:
Customer Reviews: 4.2 4.2 out of 5 stars (15,506)
Brand Name: API
Number of Packs: 1
Unit Count: 1 Count
Manufacturer: Mars Fishcare
UPC: 317163030875
Number of Items: 1
Global Trade Identification Number: 75
Included Components: 1 Bottle 8-Ounce
Item Type Name: Aquarium Algae Remover
Model Number: 87C
Manufacturer Part Number: 87C
Liquid Volume: 4 fluid ounces
Item Weight: 2.4 ounces
Item Form: Liquid
Pet Type: Fish
Target Species: Fish
Allergen Information: Apple Free
Frequently asked questions
If you place your order now, the estimated arrival date for this product is:
Sunday, Oct 11
Yes, absolutely! You may return this product for a full refund within 30 days of receiving it.
To initiate a return, please visit our Returns Center.
View our full returns policy here.
To initiate a return, please visit our Returns Center.
View our full returns policy here.
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Top Amazon Reviews
Size: 16-Ounce
Style: Freshwater
I picked this stuff up after going through 3 algae blooms in my 10-gallon tank (including one really bad one, couldn't see two inches past it, and the other two being much more tame). Now, I've read MANY mixed reviews on this product before making my purchase, and I have one thing to say. This is basically Weed-B-Gone for aquatic environments. It's made to kill algae. It's safe for fish IF USED RESPONSIBLY. We've treated two tanks with this stuff: a 60 gallon, and 10 gallon. No fish died. The 60 gallon: heavily infested with algae, specifically the brown hair algae. Applied the recommended dose (1 tsp per 50 gallons, we did a full dose). In the tank live two Convict Ciclids, two loaches, two kissing gourami, one minnow, and one otocinclus catfish. The tank itself is very well established bacteria wise, and has an appropriate canister filter going with four sponges and bacteria media. The lights on it are low-light, with one low-light grower. NONE of the fish were affected in any way shape or form. The 10 gallon: houses my one Oranda goldfish, along with 7-8 trumpet snails. Previously had ghost shrimp in it, but took them out prior to treatment, then ended up dying from separate causes (put three in a bowl, two died, the rest were killed by the stress of my goldfish chasing them and trying to eat them, I don't plan on getting any more, lol). As I stated above, went through three algae blooms/cycles before I bought this, and has an AquaClear 30gal. filter going with two sponges and bacteria media. The light on this one is a 96wat four tube grow light. The light penetrates a solid inch into the gravel, it's intense. WHEN I DOSED MY 10 GALLON: bottle says 1ml/10 gallons. From what I'VE been personally taught from my boyfriend (his 60 gallon has been running for 10+ years with absolutely no problems), the more gravel that is in the tank, less water; resulting in a smaller dose. I put HALF of 1 ML in the tank. My goldfish is UNAFFECTED, and my snails are as happy as could be cruising around. After repeated dosages, and even one dose being a full dose, my fish is fine. And now after about two weeks, I've seen NO new algae growth, AT ALL. I'm going to continue treating the tank, as it is planted and the algae has taken a liking to the plants, but as far as I can say, nothing has perished in my tank using this product, other than algae. With more heavily infested tanks: from the 60 gallon, it's petrifying to watch. When you treat it, the water will cloud up almost IMMEDIATELY. And it is and was scary to see it happen so fast. It was back to normal clarity overnight. Further research into this also relieved that the chemical diminishes in 24 hours, being completely gone by 48 hours. Example: I haven't changed the water in my 10 gallon since I've started using it. By the amount of chemical I've put in, I'm positive my fish would've been long gone by now. But he's still in perfect shape and health. Everything being said: use this with CAUTION! This is not a magical algae fix (well, was for us....), this is made to kill algae, and I'm sure with inappropriate usage, will kill a lot more than algae, including what is printed on the label. When you put this in your tank, the amount used is VERY important. Algae is still a living plant, living plants produce oxygen, if you have enough algae and do a large enough dose of this stuff it will have such an immediate impact that you will BASICALLY suffocate all of your fish. If you have any doubts about getting this product, find something else. And if you get it, use your brain. It's easy to over-dose, and some things just don't work with some people. In my case, I began with a half dose, because my tank is one of the fairly smaller ones, and I wanted to see just how my fish reacted to it. I gave it a day, then repeated the half dose, waited, continued with a full dose over the course of a week and a half. It's not the products fault, as it's working BEAUTIFULLY for our own tanks and MANY others. ETA: After moving twice and unfortunately losing my entire colony of snails, I've finally got only my 10 gal up and running as a snail tank right now. (It did have a Beta in it, but he passed away.) It was having some problems with Algae, so I slapped some of this in it, with previous encounters working just fine I didn't have a second thought. When I had lost my Malaysian Trumpet snail colony, I searched high and low to get some more and restart. I did, but the Malaysians I have now are.... different from the other Malaysians I had preciously (these are longer, have a sharper pointed shell, and are overall lighter--my previous ones were darker, larger in width, and had a more blunt pointed shell)--my new Trumpets reacted to this product, and after monitoring them for about 20 minutes and quick reacting, was able to save most of them and get the Algaefix out of the water. I don't know if these snails are just a slightly different variety of Malaysian Trumpets (the physical appearance tells me they DEFIANTLY are, but I haven't researched deep enough to be sure) but they are EXTREMELY SENSITIVE to this, and WILL kill them. So if you have ANY kind of crustacean/snail, USE WITH CAUTION! I can safely say that if you have my first "variety" of MTS, they're cool with it, but this second colony threw me for a huge loop. ETA 1/5/2015 My 10 gal planted became heavily infested with pest snails that came with a Banana plant, and I can safely say, large doses of this promptly got rid of all of them. (One large initial dose with filter off, then two more large doses after that 2 ~ 3 days apart!)
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Reviewed in the United States on May 15, 2013 by Stephanie Johnson
Size: 16-Ounce
Style: Freshwater
Ok so I have been battling some really nasty black algae for over a year. Otherwise my aquarium is spotless and the water is already crystal clear before I even bought this. The algae that I have is only on surfaces like rocks and so forth. Not in the water. I have been dosing with peroxide and that does help but this stuff is actually killing my algae. I have lost NO FISH and have used this stuff every 3 days for the past few weeks. I haven't even had to scrape my glass. The water is still spotless. Does not make it cloudy at all. I wanted to point out though that if you have a lot of algae and then you use this stuff then you absolutely MUST do a water change. I would do at least 50% or more. Why? Because when you kill algae the residue is toxic to your fish and so then they will die and you will blame this stuff when in reality it is your fault for not doing a water change. It is the dead algae that is killing your fish. Not this product. Same thing if you were to use peroxide. I can easily say that this works about 2-3 times better than peroxide which is really saying something since peroxide does kill most of it. This is some powerful stuff. I have fish fry and the whole bit. Nothing is dead. Also, it is important to say I have a planted tank and that all my plants are fine. Even my moss which is super sensitive to peroxide, but does fine with this stuff. If you have algae on your plants you will find that your plants will have some holes in the leaves. That is not this product killing your plants but rather the algae is dying and your plants have holes because of the algae was killing your plants. So trim your plants after you use this stuff to get rid of any leaves with holes and then your plants will bounce back. This stuff is expensive but you don't need much of it. And since it works better than anything else and is simple to use I guess it is worth it. Just follow the directions AND DO A WATER CHANGE. If you don't then your fish will probably die.
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Reviewed in the United States on March 12, 2025 by K W
Size: 16-Ounce
Style: Freshwater
I set up a new tank within the last few weeks and my algae got OUT OF CONTROL. I’m not much of an additive girlie but I did a 70% water change and filter change and still green. First pic is after the water change too. I ordered this, had it in the tank by 5:30pm and by 7pm it was crystal clear (second pic) I’m never one to write a review but I am unbelievably impressed by this product and the effectiveness of it!
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Reviewed in the United States on August 17, 2026 by Marlee Lakernick
Size: 16-Ounce
Style: Freshwater
Worked really well the 1st few uses. Stopped working well after a some time. Longevity is about a week of algae control. But its easy to use and the price is good for the time it did work (water clarity was good). I think my tank is just exposed to too much light.
Reviewed in the United States on February 6, 2026 by Brittany
Size: 4-Ounce
Style: Freshwater
Holy crap this stuff works FAST. I have been battling an algae bloom in my 6 gallon Beta tank. My poor mustard beta couldn't even see me to come get food. I tried everything, including snails, corys, shrimp, and lots of live plants. I added an extra filter and tested water quality daily. Nothing was working and since the tank was otherwise very healthy, I felt stuck. When I finally created a blackout environment for 3 days and it still didn't help, I order this stuff. I put a couple drops in, and went to run errands for a few hours, and when I returned the tank was crystal clear. My Beta (Artie) was dancing infront of the glass and the little corys (Click and Clack) where skittering around all over the place. Its been 2 days and everyone seems super stoked. I immediately added a few drops to my other tank, and this morning both are clear. Dont wait like I did. This stuff is safe for small aquariums as well as large ones and its the only one I could find that was safe for live plants.
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Reviewed in the United States on August 28, 2026 by Ashlee
Size: 16-Ounce
Style: Freshwater
15 days ago, i used this product the first time for my 40 gal turtle tank. I poured in full lid of algae solution from this bottle into water. ( very small lid ). The next morning, eyes from 2 of my turtles swollen real big, they could not open both eyes. the mouth also infected. Both of them become very lethargic, not moving, not swimming , not eating, difficult breathing. I sat at the table and watched them all night . They were struggling for each breath.I prayed for them not stop breathing.. i was not able to find a vet that night. The next day, i bought turtle eyes drops for them. This medication seems to help. Harry turtle started swimming, the next days, he ate some turtle food. My other turtle RON, remains sick, the swollen from her eyes went down, she was able to open both eyed but remain not eating for the next15 days. Her mouth is still swollen. Today,I took Ron, my turtle to see a doctor . He gave her a shot for viatim A,D AND D+ shot. Dr said to observe her. Doctor’s charge is $115.00 for this visit. 17 days now, Ron’s eyes are still swollen, mouth is sore. He can not eat anything, even his favorite chicken. I am afraid Ron is blind. He used to chase after his food. Now i am using algea light instead of algae solution. DO NOT BUY THIS PRODUCT, IT ALMOST KILL BOTH OF MY TURTLE.
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Reviewed in the United States on August 21, 2025 by Kim Doan
Size: 8-Ounce
Style: Freshwater
I have a 40 gallon. It is heavy planted with jungle val. Unfortunately it killed the black bearded algae along with all my live plants 😩 my jungle Val’s that I worked so hard to grow were destroyed and melting breaking off. Thankfully my fish survived, but would not recommend to anyone with live plants!
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Reviewed in the United States on June 26, 2026 by Maribeth Ruiz
Size: 4-Ounce
Style: Freshwater
I ordered this because I was having a really hard time controlling the algae since I set up my new tank. Out of all the products I considered this one seem to have the best reviews. The first picture I attached was after I did a 25% water change,then added the solution at about 9:30 AM. The second picture was at 7:30 PM the same day.I would definitely recommend this product. It worked great and I am writing this review two days later my tank is still crystal clear and all my fish are alive.
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Reviewed in the United States on September 8, 2026 by Sondra Whitney