To all new growers dont let it get you down that alot of guys say you have to have a carbon filter or your fucking neighbors will smell it while its growing and being dried out, thats bull shit and there are other ways around it, i dont have the money to blow on a 250 dollar carbon filter and inline fan and thats for a super cheap one!!! there loud from what i hear you have to instal them there pretty heavy from what i understand not to mention you cant run that shit all the time so you have to buy another timer to progam the carbon filter into it plus ducting and other shit thats 300 dollars extra i dont have!!!!!! and noise and extra electricity i cant waste so i got the ONA blocks and ona gel. it works and i dont work for ONA! i just was so damn worried after spending 900 on a light, soil, beans, nutes, oscilating fan, water and other grow suplise that id have to shell out another 300 i didnt even have for a carbon filter fan combo, but the ona works i order three ona blocks and one jar of ona gel, it was like 50 bucks for all that so far two of the jars are open and completely working, no smell what so ever it went from crazy skunky to now nice and fresh, i have to admit at first it was a little weird the ona alsmot made my nose a little stuffed but that wore off i sleep with two 5 feet in front of my bed and dont smell anything. ONA works to all growers out there that are crazy worried about the smell like i was and thought the only option was a carbon filter i couldnt afford ,make sure you get enough though because from what i understand one ona block only last about a month and flowering last around 2 so id advise atleast getting an amount like i did and mine are working for seven stinky plants going on 5 days now and i can say they work. OH also from what ive read the bud comes out with no smell...... this is what people say but you know im sure it still smells when you break it up but it is not suppose to make the buds any different or any less dank, ill take smelless bud any day over neighbors smelling it , peace all