sentinel mef 1 question ebb and grow

Discussion in 'Hydroponics / Aeroponics' started by rollyouron, Jan 27, 2013.


    rollyouron Well-Known Member

    I just bought one these and put it together. I'm a little confused on how to set up the control unit though. I understand how to set it to flood and how long to flood for, but for the life of me I can't find a clock so even though I can set it to flood every 3 hours for 15 min I don't know when it will start. Should I just plug the control unit into a timer that turns it own a 6am and turns off at 12 midnight since I'm not going to water with lights out? Sorry if this is a dumb ass question I'm new, and this is my first ebb and grow.

    Land Member


    rollyouron Well-Known Member

    Thanks. That's the instruction manual that came with the unit, and says nothing about setting a clock. I'll call them today.

    AWayOfLife420 Member

    any update? i just ordered one of these units myself

    NoxMetus Member

    Any updates? I'm ordering one of these.

    chickenthr33 Active Member

    Ordering one of these soon, hopefully be setting it up within a couple weeks but known to get lazy... would love to exchange experiences. A little concerned about roots possibly clogging the hole on bottom due to a possible siphoning effect it would have during draining? New to hydro, somebody mentioned this in another thread and it made sense. I was planning on a CAP ebb and grow at first and some screen fittings to prevent roots from following the drain lines but they come out the side on the CAP and flora versions, not sure what a similar idea would be for the bottom drain.

    I'm also curious about plant size in the 2.5 gallon buckets, I've gotten my plants to about 4 feet usually and they are normally rootbound in 5 gallon plant warrior pots (which have that cone in the middle so in reality they are probably 3.5 gallon?). I've always used Pro-Mix so I'm wondering if this setup with SunLeaves Grow Rocks is going to end up being less space and they get rootbound even faster (or at least, fill up the bottom pot and risk clogging the drain hole).

    I was tempted to get the CAP Monster 5 gal version, or the Titan Controls Flo-n-Gro which has 4 gallon square pots but this Sentinel one really seems like the best quality and I like how it's easy to convert to a drip to waste which I think I might end up using eventually. Also don't want to end up with larger containers than I need. I just wish they gave people more options when they buy this stuff, we shell out around $430 without a reservoir but we can't have any options for pot size :(

    (818)MedicineMan New Member

    In the manual under "operating instructions" it says set the timer by aligning the white arrow on the timer face to the time of day. That system appears to use the timers that you push in or pull out pins to set the program. You set the time of day by aligning the arrow on the face of the timer to the actual time of day. Make sure to get the am / pm part right.

    chickenthr33 Active Member

    The Sentinel is a digital controller... no mechanical timer afaik.

    rollyouron Well-Known Member

    I have an update. I'm waiting on my mother plant so I can clone. It will be about another week. I've been test running it for 2 weeks with no plants, and it has run flawlessly! It has some really neat features if you want to use them. I thought it was a little complicated, but after playing with MEF 1 control box it is simple to figure out. I misinterpreted the direction when I first read them, it has 24 hour and a day setting. In my brain I thought it meant 12 hour and I didn't want to feed lights out. The timer says 24/day and you choose which one. As long as your lights are on it will to continue to feed. I have mine set to feed every 4 hours for 15 min.
    In the day mode that's what I have mine set on, when your lights turn on it wakes up the MEF 1 controller on and it starts to flood 15 seconds after lights on.

    rollyouron Well-Known Member

    I'm new too. As far as roots clogging, it has some kind of a filter/screen that covers the pipe.
    The buckets seem to be a nice size, but then I haven't grown anything in mine. Im limteted on space anyway, so I don't think 6 5 gallon would fit as well in my grow/flower room 4x4. As far as a reservoir I have it in my clone/mother room 4x4 and I didn't want to use a 55 gallon drum, because I'm only running 6 pots. I found a 25 gallon that works really well.

    chickenthr33 Active Member

    I'm about to FINALLY order my system. I was about to order yesterday, then realized the damn thing only comes with 6 pots, then I noticed there were 2 different ones on every site, with price difference over $100!! I was very confused, so I called hydrogalaxy and also called the phone # on Sentinel's site and had them confirm that both products appeared to be the same thing, just different pricing/distributor most likely.

    If anybody is interested in buying this system, don't buy it for $589.99, you can find it around $430 -

    I nearly broke down and just ordered a cap system, but I really like the alarm system on this and it just seems well built. I really don't want 50 gallons of water flooding in an upstairs room :)

    Disadvantage of this system is only 6 pots and no reservoir. I was going to just do a rubbermaid brute setup but it appears as though I'll be up around $80 by the time I pay for the can/lid for 50 gallon so I guess I'm going to bite the bullet and just pay the $105 for the 55 Gallon Reservoir w/ Lid RES255 for $102.91

    bowlfullofbliss Well-Known Member

    lots of people just use a large plastic trash can from Lowes or Home Depot, you can get one for 1/3 the price. I won't bother to buy another one again from a hydro store. I've seen the trash cans in 32 gallons and 55. I personally only run like 35 gallons in my 24 pot ebb-n-grow, so having the large 55 isn't even necessary.

    also wanted to mention that it is wise to buy and install a heavy duty pond liner in the room that your system is in. These things can fail if the slightest thing gets out of whack, lots of moving parts with the little float valves and whatnot. I put a liner in both rooms, I think they cost about $100 for a big one. you can use 2x4's to make edges for the liner around the area your water holding pots and res are in.

    chickenthr33 Active Member

    Thanks for the quick post, I decided to check here one last time while deciding. I've never been diagnosed with OCD but god damn I must have it cuz I been working on this order for a month. Living in the middle of nowhere and having to buy everything online doesn't help :D

    How much do your plants drink? I've seen several people say that it's not uncommon for theirs to drink a gallon or even more per day especially during flowering, that would only give me 2-3 days out of a full 32 gallon res for 12 pots.

    Amazon sells the 44 gallon rubbermaid brute for $46, plus $20 for a lid. 55 gallon rubbermaids for $70 + a lid so either way I'm not really saving if I go with the big daddy. Hydrogalaxy has a 55 gallon with UV protected lid for $103

    asfixious Member

    I have the MEF-1 with the 6 pot expansion kit. It has a built in photo eye that will stop it from flooding when lights are out as long as its set to the day setting and not 24 hr setting. push and hold the day 24hr button and it will tell you what setting it is in. The up down buttons change the setting. Hope this helps

    captjimmy Member

    has anyone gone to harvest with one of these yet? I got a little compulsive on ebay and have OOODLES of sentinel stuff and would really like to try this setup ?

    p0opstlnksal0t Active Member

    Are these still produced? I can't find kits anywhere

    digging Well-Known Member

    These were great systems, except the pumps were only either 12 volts or 24 volts.

    IMG_0450.JPG IMG_0435.JPG IMG_0456.JPG
    Last edited: Mar 17, 2017

    p0opstlnksal0t Active Member

    It looks like I'll be stuck with the hydrofarm grow flow controller. It has a few similarities the the sentinel

    adower Well-Known Member


    Shawndeadhead Well-Known Member

    I found these guys that still seem to sell the sentinel ebb and flow system your asking about, it shows a price and it allowed me to add to my cart so looks like they still have them in stock though complete system was $599 I believe.

Share This Page