Kolar Labs Crystal Cal Activated Carbon – Small Jar, Activated Charcoal for Aquariums and Fish Tanks

Bombed my tank for worms. The value on this jar was great. 3 lbs. The worm treatment wanted me to use 1 lb per 50 gallons. Soni sued 2 lbs and have another lb or so for emergency. Make sure to give it a good rinse. As you would for any activated carbon.

Great value--lasted a couple of years for our 20-gallon tank. Did the job! With a name like Kolar--it's gotta be excellent! (My former surname). :}

Good quality and delivery on time

Buying filter carbon cartridges for both canister or aquarium filters that hang on the back can get expensive. This is a way to reduce the cost by buying the activated carbon in bulk, then purchasing mesh zip up bags to fill. (Bags are not included). On jar of this carbon will fill a lot of bags making the cost of the filter change nearly nothing. I have noticed that it takes a long time to rinse out this carbon though. Seems to be a lot of dust. It takes me about a minute or more of rinsing to get clean water through it. I have had other filter carbons rinse clean in 10 to 15 seconds. Overall though it works fine with just a little more work up front.

Very high grade carbon. Needs very little rinsing. I was really impressed. I had a problem with hair algae, and this product pulled out a lot of dissolved organics from my reef tank in just a few days.

Best deal for the money

This is great value filtering media .it works perfect at removing foul smell from aquarium and water is crystal clear. Clean water - healthy fish

I put this in a fill bucket for my garden to remove chlorine from the water. I don’t have a chlorine test but I did see all the slimy algae disappear leaving crystal clear water. Meaning it at least absorbed all the fertilizer from the water (and I’m assuming the chlorine too). For that reason you shouldn’t add it directly to planters though. I added it loose but soon realized and aquarium strainer bag would have been better to make it easier to change next year. Next time I will. For my purposes it was easier than a standard carbon filter and a tube because that kept clogging from buckets that were even slightly dirty. If my hose hookup was closer then I might have attached a regular filter to that or perhaps a sediment filter and then a carbon filter.