thanks dude. since your word is pretty much law around here,
YOU ARE THE FUCTING MAN,DUDE!!!!!!!!!
eeeek.
Please, no. While I appreciate very much that you value my input, I absolutely cringe when folks say stuff like this. I absolutely do fuck it up and OFTEN. 'Thanks Al' will do.
i'm printing out plans for a flood an drain table
[...]
they seem like pretty easy set-up to maintain.
Watering systems get no easier to set up and operate than floods. Impossible to clog. All that can go wrong is a pump or timer failure. If you keep a spare pump handy (and they're not expensive), you're well covered.
know where i could go to actually learn how to use it?
well, yeah... probably right here.
as far as what type of medium is best,
how often should i flood and drain,
Depends on how you care to work in the op. Pots stuffed with media which holds a bit of water like rockwool floc and Fytocell are good for stoned slackers (like me) who may not want to look in on the op every day. If a pump or timer fails, there's enough water stored in the media to carry the plants through for a day (and a bit more with rockwool) until you have a chance to correct the problem. However, highly absorbent media does not allow you to flood frequently without drowning roots. 1x/day is enough for RW, 3x/day for Fytocell.
Media like clay pellets don't hold as much water. The large airspaces between pellets allows you to flood more often, starting with about 5x per lights-on. Since the nutes in the tank are being constantly aerated with an air pump/bubble curtain, freshly oxygenated nutes can be run through the rootmasses more frequently than in highly absorbent media, increasing vigor and growth. Simply flooding and draining also draws more air into the media as when the flood level falls, air replaces water in the medium. It's almost impossible to overwater in pellets. With large, mature plants, you could conceivably flood 1x/hour for 5mins per flood.
However, pellets are hard to dispose of and while theoretically reusable, are a total bitch to clean fully free of old root matter from the last crop. If you don't fully clean & sterilise pellets before re-use, root diseases can be passed form crop to crop.
Clones in RW cubes must be nested in the pellets so the cube is about 1/2"
above the flood level. The cube itself must not be allowed to be saturated. Plants in RW cubes just introduced to pellets should have the pellets around the cube (NOT the cube itself) hand-watered from the top for a week or so until the roots have knit down into the damp pellets.
Just about any centrifugal aquarium type water pump will do from the smallest 400L/hr pump (I get those for $11 ea, shop around) on up. Cheaper pumps don't last as long as more exxy ones which move a lot more water, but you really don't need a pump that moves oceans. All your pump needs to do is flood the tray to the overflow tube level within a few (3-5) minutes, then shut off.
A big pump (I now use 2000L/hr pumps) IS nice for when you're draining the tank, if you have installed a valving system like this depicted, to make draining easy. A bigger pump drains the tank faster. Just switch the valves to the drain position (close #1, open #2) and go get a coffee. When you're done with that coffee, the tank will be empty and ready to be cleaned & refilled with fresh sauce. Be sure to switch the valves back to the operating position or your new tank of sauce is going down the gurgler when the timer next runs.
should i flood and drain only while lights are on
Yep, no need to flood during lights-off. The plants transpire very little water in darkness as photosynthesis has halted. The amount of water contained in the rootmass will be sufficient until 'morning.' The last watering should happen no later than an hour before lights-off.
Hey Al,
I have a few questions on your cloning method.
How is the ventilation in your box setup? I know you keep the temps up with a heating mat. Do you ventilate the box? Intake? Exhaust?
What's your thermostat connected to(intake, exhaust)? What is the temp/humidity inside your clone box?
Well, the heat mat actually is only responsible for keeping the RW cubes warm.
The air is kept warm by waste heat from the fluoro ballasts.
Not seen in this pic, and for winter use only, I do have a very small (120mm), cheapo desk fan in the box now, mounted above the fluoros and pointed upward. This evens out the air temp within the clonebox so the warm air at the top of the box is mixed with cooler air from below, around the clones. Air temp is set by the thermostat (can't be seen in this pic, it's mounted down low, at plant level), which switches the 100mm exhaust fan (seen in upper left on back wall of clonebox) on when the temp reaches 30C. When the temp has come down to ~28C, it switches off until the temps come up to 30C again.
Humidity in the box isn't as critical as temp. The RH in this clonebox varies but the temp is bang-on 30C +/-1C at all times.
I've been looking for the thermostat that AL is using and cannot find 1 in north america...seriously...lol...Does anyone have a link to where I could find 1 similar online (preferably in Canada)?
Thanks.
The
thermostat I use is sold in Australia at Jaycar Electronics stores. You can order it online and they ship worldwide.
The maker of the tstat is 'Computime' (model 098A) if you care to try to find it locally. the main reason I love this tstat so much is that it can directly switch 240V AC mains devices, either for cooling or heating. I'm sure there's an equivalent in Nth America or the UK if you can't get this particular one. Common HVAC tstats often can't switch line voltage, rather are designed for 24-36V control voltages found in central heating systems. Make sure whatever tstat you select is capable of switching devices at your local line voltage.
The size of the clonebox isn't terribly critical. My clonebox is fashioned from an old plywood shipping container which is roughly 800mm tall x 600mm deep x 1m wide, should you care to know. There is no intake fan, just a passive intake down low on the back wall, covered with flyscreen. I cover this intake in winter (bit o' packing tape) and allow intake air to come in around the poorly fitting front cover of the box.
Is perlite a good substitute for the fytocell in this setup? I was reading a previous post in which I believe you said you used straight rockwool floc in your pots, but now you use the fyto-floc mix. Why did you switch to fyto-floc...
Yep, perlite will work pretty well. It can escape the pot drain holes, so a 25-50mm layer of floc, tightly packed in the bottom of each pot, keeps the perlite (or Fytocell) in the pot while allowing water to flow in and out of the pot during flooding.
RW floc is HIGHLY absorbent, better than a sponge. It's actually too absorbent and you have to use care not to allow it to be saturated. You can only water pots of RW floc 1x/day without inducing overwatering symptoms, especially in small plants. Fytocell can be flooded more often; I'm flooding plants 3x/lights-on post wk2 now.
It's important to note that the RW & Fytocell in my pots isn't actually mixed, as such. The floc is packed in a 25-50mm thick layer, very tightly in the bottom of each pot to act as a filter. Keeps the Fytocell crumbs in the pots. Fytocell has a very high air content (40%) and tends to float. When the layer of floc is wetted, the pots won't float.
I was wondering how low the temp flowing through the cooltubes can be...I am planning on either bringing air from outside in the winter or exhausting it ...say -15 degrees celcius intake.
The colder, the better! Mind you, I think I would not draw air in at below -100C as this might shatter the HPS tube envelope. Of course, the only way you'll get temps low enough to do any harm is to use liquefied air on your intakes, something you're probably not going to do.
wll the air being exhausted produce steam(would look a bit shady). What could i do to prevent this...
If the cooltubes have a closed air circuit (drawing air in from outside the grow & dumping it outside as well), it will not be picking up the humidity transpired (or scents) from the plants and so will not produce any steam, even in very cold temps, unlike air from your clothes dryer or exhaust gases sent up a chimney from a natural gas water heater.