Electric timer that less than 15 min. increments

Help can't find a timer that is program able to 2 minutes on, then 20 minutes off or something that way. I found one, but they want $84 for one. The reason i want one is because the box is in the basement, with a power intake, and exhaust fan, i have to leave the windows open for the plants to breath co2, if i don't the leaves droop, when i open them the leaves go back to normal. Winter is coming, it's 20 degrees outside, so with them windows open the heater i got in the box runs and jacks up my electric bill. The timers i got the exhaust/intake fan on all have 15 min. increments, man that pulls in a lot of cold air. My idea is to have a timer the runs for 2 min. then shuts off for 20, then runs for 2 min. Not a big grow room so it doesn't need 15 min. air exchange. (picture is attached by the title of this message) Anybody know where i can get one for about $40 tops?
Thanks

Hate to say it, but I believe the $80 CAP unit is your best bet. I'd love to be proven wrong, though.

Really? They that hard up for CO2? I have never heard of them drooping that fast over CO2, I bet its the temps. If it is the CO2 there are some DIY options for generating it. I have never attempted one as they all seem to be messy and not worth it, but it seems like it would help you out.

Yeast/Sugar Water isn't messy as long as you don't overfill your generating container with sugar solution. the stuff tends to almost double in volume when activated so only filling the jar up 1/3 of the way works fine.

When it comes to timers you have to spend the money when you want a lot of different settings or adjust what you are doing.

I can't seem to find my digital timers right now, don't ask me why, I have at leat 2 of them and keep them plugged in to keep the battery charged up in them.

Go to Lowes and look at the Timers in the phone wiring section. Look at the $20 ones and you may be able to use that. It has like 21 settings if I remember correctly. You can set it for 21 times during the day and the cool thing is after that you can have it repeat 7 days of the week, so just becuase you used all 21 on/off up doesn't mean you are done, just have it repeat the rest of the days in the week.

That is your option, go there and look at the $20 timers or spend the big money on one.

That was the conclusion I came to years ago.

good luck

i got a electronic weekly timer pretty cheap of ebay dunno who its made buy but it says "automan" and "walk easy" on it, it says it can turn on and off at 1 min intervals, but i dont know as its so fucking hard to program i gave up on it, and im usually a super nerd with gadgets so i got reaaaaly pissed off at it, i wana use it so bad but instructions are shit

I gotta say, that cap timer is way cool, and it gives you a LOT of control, you have between 1 second - 40 minutes on time and 1 minute - 8 hours (I think) off time. Worlds if possibilities I personally keep two just to have in hand, you can never have enough timers