Black Swan 09020 ZAP Drain Pipe Opener, 32 Ounces, Heavy-Duty Formula Clears Clogged Drains & Waste Lines, Thaws Frozen Lines, Disintegrates Organic Matter, Safe for Septic Tanks

Forgot drain-o or any other type of drain cleaner you can think of. This stuff is incredible. I like to run hot water in my plugged drain first. Wait for it to all drain out, then pour a little of this in and let the magic happen. Be careful, it is acid! It will stink and dissolve organic material. But it clears drains within 10 minutes. Let it sit in the drain for a little and then slowly run hot water over it until it’s all gone and you will see that your drain should be free flowing again.

Works great on backup sinks

Best cleaner on the market! A must buy!!

The drain cleaner works great for tough clogs

Be VERY careful and follow directions. I have tried many drain products thru the years and the acid ones will work where others fail.

If you want to destroy all of the pipes in your home, use this! If you want to spend a couple thousand dollars on a plumber after using this, by all means, USE THIS! This is nothing but pure acid! It literally burns right through metal pipes! No pipes left in the walls or ground or underneath your sink or wherever you use this. Stay away from this! You've been warned. Smh.

This stuff works like no other. Our shower drain, 25 years after construction, was full of hair and soap. One or two prescribed doses does the trick. This is after years of the store-bought drain cleaners and online lye-based cleaners just muddled along. Those lye products can loosen the debris, but just enough to slow the drain or, worse, harden into a solid clog.This sulfuric acid breaks through without clogging. (Though instructions and other online advice do caution severely, don't follow other products with this strong acid.) Follow every caution and warning in the instructions and online advice. Google sulfuric acid in drains. There are some disasters out there -- this is the real thing.Buy the heavy black pvc coated, chemical resistant, elbow length gloves, and use good eye protection. If it will eat through what's in your drain, it will eat through your skin and eyes. It sort-of "explodes" up out of the drain when it interacts with all the crud you're trying to get rid of, so stand back. And use a fan and exhaust fan so you don't breathe the toxic fumes.But it works!! Nothing works like this, and I think we tried them all before.If you are competent to handle dangerous sulfuric acid, you'll be pleased with how well this stuff works....ADDING THIS IMPORTANT SAFETY CAUTION ALMOST A YEAR LATER....Just to reinforce the safety cautions I see in the few negative reviews here, and on google regarding sulfuric acid in drains .... If you have used lye-based products and consider using this acid, be absolutely sure you have washed all of the lye out of your drain multiple times before using even a tiny dose of the acid. If there is still lye clogged in there (apparently this happens commonly, based on reviews and other online disaster stories), the acid will explode violently and dangerously up out of your drain with amazing force. You'll be cleaning your walls and ceiling for hours, if it doesn't get in your eyes and send you to the emergency room. The company seems very responsible to warn us in their instructions on the bottle. I'm just saying, please take these cautionary tales seriously.

Clogs that would not yield to conventional lye-based drain openers were quickly cleared with a satisfying "woosh" as soon as I poured this acid-based product down affected drains. Multiple sinks and a bathtub/shower are usable again! Yes, you have to take precautions with this product (read the label). Yes, there will be a temporary "rotten egg" smell as the acid clears the drain. But this product is absolutely no joke and may save you a plumber visit.