Fan Size

Hey guys, I am a first time grower, and I am confused about a few things.

1. I am getting a 80 cubic foot tent, but the fan that comes with it is 440 CFM... which means it's gonna be doing a full air exchange every 10 seconds... I am ok with that during veg, but I am going to run CO2 during flower, won't that fan suck the air, along with the CO2 right out therefore wasting it? Is the fan supposed to always be on?

2. I am using a digital ballast, 600w MH during veg and 600w HPS during flower, so I assume it will be hot. Also, is 1 600w HID enough for a tent that is 4'x4' at the base and 5 feet tall? I will be using soil, so 4 feet tall... The HID also sits in an umbrella reflector, so I would say that eliminates another 8-10 inches... so 3'2" or so... how tall should I veg? I was thinking 15"... but will that be too much? Also, I heard that a 600w HID should be about 18" away from the flowers... is this correct? I will aslo be running two 13w Advanced Spectrum LEDs throughout the entire grow.

3. I am going to make my own CO2 to save money. I was told to fill a 20 oz. bottle 3/4 way with water, then add 2 cups of sugar and 1/4 tbsp of yeast... Is this legit? Thanks.

This is the setup I am looking at... http://growace.com/product_info/ga-600w-specialist-series-grow-package.html

Avoid using a tent if you can! They introduce a lot of issues with heat! I would also max out my lumens by going with a 1000w DIGITAL ballast and an air cooled light.

What should I use if not the tent? I want the grow to be fairly discreet so hidden, and smells being taken care of are my concerns.

Hey there mate and welcome to RIU



You should keep in mind that although your Fan is rated at 440CFM, you should expect a significant drop in pressure once that thing is connected to a carbon filter.

^^ what he said ^^

Also, your gonna want either a taller tent or air cooled reflector. My tent is 5 feet tall, and just barely tall enough to use with my 400w hps. Also keep in mind you need space up top for the filter and stuff.

You can find something to reduce that fan speed, like a rheostat, and find the least amount you need to keep the temperature within range during peak temp period. You want to keep the CO2 obv, so its a tradeoff with airflow and temp.