As stated previously, this will be a hydro grow using a four gallon Flo ‘n Gro system, and chances are many of you are asking, “What’s that?????” Well, in its simplest form, it is a modular enclosed version of an ebb and flood system (no table) with a light tight net pot container.
The advantages of a commercially built system of this type are convenience, and the ability to locate the reservoir at the same floor level as the grow modules. This could be needed if you have a grow area with limited headroom. Not the height of the tent, but the height of the room where the tent and/or grow area will be located.
Disadvantages? They cost a lot of money. Commercial versions of this system are available in the $500 to $700 price range for a twelve module system. Good luck finding a smaller system, say, like, four modules. And having your reservoir located at the same floor level as your plant requires some fairly complex controllers, valves and pumps, which could lead to long term reliability issues. Not only must the flood stage be powered, but the drain stage must be mechanically evacuated as well. And precise flood level control may be more complicated than a manual system like the one I have assembled.
My system has two moving parts – a simple mechanical timer, the (24) hour push-in tab type with (96) individual on / off settings of (15) minutes each; and an inexpensive hydro pump. For about the last ten years I have used the EcoPlus series of pumps (typically the ECO-185, could go smaller with my single-plant grow style) and have yet to have a pump fail. The only maintenance needed is a simple disassembly and cleaning at the end of each grow cycle.
I've used almost all types of hydro systems, and thistype is the most reliable I have ever used. The reservoir has enough reserve capacity to support vacations or long weekends with no worries. I can regularly take trips of seven days or longer with no worries that I will come home to a disaster. I just need to time the trips to periods when I will not need to modify nutrient mix or adjust light height while I am gone.
Many growers are scared of leaks in a hydro system, as they should be. Caution must be taken at all times to insure your connections are secure. Like the time I disconnected my flood and drain line from my flood table to clean the inside of the table. And forgot to reconnect it at the end of the job. And the next flood cycle pumped twenty gallons of water into the air and onto the floor. And the second flood cycle was with a dry pump which burned out. Fortunately, my grow area was a utility room with a floor drain, and I had a spare pump, or disaster could have resulted. But not really a “leak”.
Point to be taken – build an idiot proof system and someone will build a better idiot (me).
The premise behind this system is ancient – the water level. Pour a body of water and one end will be precisely the same height as the other, wherever you take it. Before laser levels were invented, plumbers and construction crews relied upon a simple flexible hose filled with water, with transparent sight windows on each end. An area of air was located at each end of the hose, and the water level in the hose was marked at an equal level for both ends. Gravity did the rest. If you hold both ends together at the same level, the water level in each end will always rise or fall to the same level. If you move the two ends apart by, let’s say, 30 feet or more, and move the hose end up and down until the water level aligns with the mark, you have reached level. This is handy for setting foundation piers at the same level, or adjusting the slope of a gutter or drain line, or any other activity that requires precise levels located across longer distances. Gravity does not lie, and will not deviate. More in a minute.
In order to make my system as failsafe as possible, a simple table must be constructed to fit over the reservoir. By taking advantage of the water level principle, and placing a simple manifold over the reservoir and on top of the table, all flood and drain cycles can be automated and precisely controlled. The manifold has no moving parts, and it totally eliminates the complex controllers, valves and timers in a commercial system. I like basic woodworking, so I go out of my way to build a nice, sturdy table that wastes no room in any direction and holds all equipment precisely. But you could accomplish the same thing with whatever blocks and wood you might be able to scrounge, find, steal or purchase.
Still scratching your head? My verbal prose didn’t quite paint the pretty picture for you? Here’s a simple hand drawn schematic that illustrates the mechanics and lays out parts and most costs as well:
Still don’t get it? Here’s an aerial view of the system being tested for the correct flood level in the net pot module (with net pot removed for clarity). Please don’t share these with any foreign governments as I used top secret drones for this aerial photography, code name Step Ladder.
When flood time is triggered by the mechanical timer (never had one of these fail either), the hydro pump turns on, and pumps water approx.. 6” to 15” up into the manifold. The flood / supply connection is made from the reservoir pump, through a ½” hose, up through the bottom of the manifold bucket, using a $7 set of ebb and flow (through-hull) fittings (1/2” supply and ¾” drain), available at any hydro store. A second connection is made very close to the bottom of the manifold through the side wall, into the side of the Flo ‘n Gro module, using standard ¾” hydro grommets, connectors and hose material. As the pump fills the manifold, water level principle (AKA Gravity) floods the grow module at the same rate; i.e., water level in the two containers rises equally. Now the failsafe – when the water reaches the desired level, an overflow pipe in the manifold returns all additional water back to the reservoir or the duration of the flood cycle. It is physically impossible (as long as gravity continues to work) for an overflow of the manifold or Flo ‘n Gro module to occur. The manifold is sealed at the top, so no foreign matter (grow rocks, poor housekeeping leaf clumps, dead rats, etc. can clog the overflow return to the reservoir. Overflow and drain occurs in the manifold which is sealed, NOT in the plant module, so clogs are not possible. Every time the flood cycle is activated, water is fed under slight pressure into the Flo ‘n Gro module. Unlike RDWC (recirculating deep water culture), this washes any overactive root mass back into the module. The drain cycle starts when the timer turns the pump off, allowing gravity to passively drain through the ½” hydro pump connection back into the reservoir. No root mass can be sucked into a connection causing problems over the length of the grow.
Another strong point of this system is that, as each flood cycle fills the manifold to overflow, all the runback into the reservoir falls in much like a waterfall. This helps aerate the reservoir to maintain a well oxygenated environment. But I still maintain an airpump, airstone, and second circulating pump inside the reservoir, just to be safe.
I’ve completed (16) single-plant autoflower grows using this system. I also adapted this design to an eight module, two gallon net pot design I used to complete several multi-plant photoperiod grows when I was doing regular pheno searches. These grows consistently generated 15 – 16 oz. yields from eight plants under a 400W HPS lighting system. Better than 1 gram per watt on photoperiods without SOG or LST.
But here’s the point I started to make before I wandered off again - Never have I encountered any evidence of even the slightest clogs or system induced leaks in this setup. NO overflows. And the only leak I ever encountered was a tiny seep / weep hole where I cracked the manifold. I was re-assembling the system after a post-harvest cleanup, and I tried pulling the ¾” hydro connector out of its grommet to replace it with one that I’d ground off most of the barbs to make the hose connections easier. Too much force, hairline crack in the plastic wall of the manifold, resulted in a small weeping leak that wet the top of the table but never made it to the floor. Lesson learned – if you pull on anything hard enough, it will crack. At least that’s what she said….
Oh … there was one other leak. I run an always-on recirculating pump in my reservoir to keep everything well aerated. I changed reservoirs to a model that was heavier construction, longer and lower than the previous. I filled it to the same old (14) gallon level as the one being replaced, because that was how much nutrients were in the old reservoir. Well, I also said this model was shorter. The recirculating pump was too powerful, and as it washed down the side, it made the nutrients rise over the top rear edge of the reservoir and onto the carpet. The problem corrected itself after about one gallon leaked out, which made the leak harder to diagnose when I discovered it the next day. So I made two design changes – I installed a T-connector and partially closed ball valve on the pump outlet to divert water in two directions; and I reduced the reservoir contents from 14- to 12 gallons. Wish I’d done this originally because 12 gallons works soooo much easier for the nutrient strength calculations I do throughout my grows.
About the Flo n’ Gro parts. The magic sauce is the blue 4 gallon bucket, which perfectly holds the heavy duty black three gallon net pot container in a light tight system. When I ordered mine from Sunlight Supply, they were listed as a four module expansion kit for the commercial system, and cost $52. I had to drill and grommet the system but that was easy with a $10 hole saw from Home Depot. Looking today, I only see Sunlight Supply through Amazon, and a six module system is listed, pre-drilled and grommeted, for $97. An assortment of connectors, shut-offs and hoses is included, along with free shipping. I suspect, if you found a hydro store to show you their Sunlight Supply catalog (they used to take orders direct) you might still find the four module $52 system as well. Single module buckets are also available on Amazon at a slight per-unit premium, but I highly recommend you purchase at least two. If I have a plant that exhibits strong vegetative growth and I feel will need more room for LST, I like to relocate the blue bucket to a corner of the tent, using a right angle elbow connector. The diagonal to the opposite corner provides a longer / wider training area. I have one bucket set up with an elbow connector for this purpose; the others have straight connectors for placement in the center of the tent.
One of the best features of Flo n’ Gro systems is that they can be set to flood very frequently. I have mine set to flood at the beginning of lights-on, and to repeat this every two hours. The minimum on-time of my mechanical timer is 15 minutes. It only takes a few minutes for my EcoPlus-185 (approx.. 3 gallons / minute) to flood the manifold and net pot / bucket. I would prefer to flood more frequently but for a shorter period, perhaps a five to seven minute flood cycle, every hour. A shorter flood on a more frequent cycle will do a better job of oxygenating the root zone of the plant, and this system does this better than most. Every time a flood cycle starts, rising water forces all stale air out of the root zone. When the flood cycle ends and water drains out of the net pot, it pulls all fresh air back into the root zone. No mechanics, no moving parts, just simple blow-and-suck action. I like it.
So if anyone is aware of a reliable, programmable timer that offers short on-cycles for many times a day, please let me know. I probably need something in the range of (20) to (24) on/off cycles in a (24) hour day, with each ON duration around (5) minutes (my current mechanical timer has a minimum on time of 15 minutes).
The final feature of this system that I’m so enamored with, is Bio balls. I’m convinced this is one of the reasons my grows are so successful.
(Who has plastic balls? Stretch Armstrong. Who has steel balls? Superman).
Go to any aquarium store and look in the filter section. Chances are they will have these little plastic balls that go inside a cannister filter, each one about ¾” in diameter. If no, kick them in the ‘nads and order from Amazon. Bio balls are designed to create a friendly environment for beneficial bacteria that eat shit and (don’t) die. The 90-count package made by MarineLand costs about $5; and is the perfect amount to cover the bottom of the blue bucket, under the net pot, with one layer of balls. Buy one package for each Flo n’ Gro container you intend to run simultaneously. If you’re diligent with your clean-up, they can be reclaimed and re-used over and over. The roots will “grab” them but they can be coaxed out and cleaned easily. I “charge” these at the start of every grow with myco’s and beneficial bacteria. Since I started this, I have never encountered a single root problem of any kind. I swear by these. Here’s the parts:
And here’s a close-up of the bio-ball. She’s a hard worker.
Next installment, Nutrients.
