A round of
for Al.
thanks.
my question today is, how do calculate the size of a res tank, lets consider a 5x5 table, 7 in high, with 4 plants in a square foot.
also lets say we only flood to 5in.
with that volume, i beleive thats approximately 295L
That's a BIG flood tray!
now that is just too damn much to be flushing down the drain at the end of the week, for one table.
Well, when I consider that I run 4x 900mm x 900mm trays (close enough to 3'x3' for discussion purposes, so ~36 sq ft lighted space), which also flood to about 4-5" and these trays are supplied by 4x 125L tanks, I'm using 500L to supply this space.
also you could fill the table with a medium(I am thinking Higromite) of some sort(i think i would prefer not to, but if it has to be done to fix the nutrient volume issue). but how much could this take up?, 70-80% volume?
if thats right, the 100 L res will do fine no?
but im not sure
If you fill the tray with media, there's nothing to keep roots from neighbouring plants from knitting, preventing easy portability of plants within the op. There would be no difference in the res volumerequirements for a tray filled with media as opposed to plants in pots of media.
I use about 5L of tank volume per plant. With this tank vol per plant ratio, I find that the nute strength remains constant even as water level drops. The plants use the nutes at about the same rate as they use the water.
Al's tables are less than 3x3 per side at the bottom which is less than 9 square feet and he uses 125 litre tanks.
You are talking about an area of 5x5 per side or 25 square feet. So it is close to 3 times the area.
For each tray, yeah.
I would say you would have to have one hell of a big resevoir for that setup 400-500L...
Yep, I think that's about right.
I chose to run 4 separate trays and tanks so I could have the ability to tailor the nutes for each 2 week phase, in particular with use of a flowering additive in week 6, but I don't really use that ability. I run all the tanks at 1400. It's also a bit hard to find inexpensive plastic tubs which are much larger than 125L. Use of multiple tanks to feed a single large tray can be problematic.
As you all know, I've had problems with Canna's PK-13-14 cooking plants when using it at the recommended dosage. I've recently gotten a reply from Canna on nutrient strength and use of PK-13-14, but they got a little confused with my query and I need to bounce it off them one more time before I'll cite that conversation on here.
And just to ask the same thing as a coupla posts ago, on my bluelab truncheon i have 4 readings measurements, EC, CF, PPM (EC x 500) and PPM (EC x 700)........
I could be way wrong, but it seems to me that there are TDS meters that measure 1EC to be 500ppm, and others that measure 1EC to be 700ppm. My Bluelab meter for example measures 1EC at 500ppm, but on the AN website, their calculators list 1EC as 700ppm.
Since you say 1400ppm, was wondering if that means 2 EC (700 scale) or 2.8 EC (500 scale)
Or am I just seeing things that aren't there? Searching the web gives me info pointing to both so it seems that EC is the value that stays consistent for everyone.
I have a particularly old Truncheon- it's more than 8 years old now, so old that it has the previous company name, NZ Hydroponics, instead of Bluelab, on the label. It also does not have any markings for x500 or x700 on it. I don't quite know why there'd be two conversion scales for EC to ppm.
yeah man!
my reasoning for putting the pellets in was because I thought just wetting the clay pellets the plant could draw water off of the water retention in the clay pellets.
Pellets hold next to no water and don't wick much.
I do have a heating pad under the grow tray but it is a regular house hold pad not horticultural. I have it set on medium which is still very low heat but enough to warm the cubes enough that they seem to like it on medium you can place your hand on it and get a nice warm feeling not to hot and not to cold I think just right.
*sigh* You can't
guess this stuff! You gotta KNOW what it's doing! If you want to use a heating pad for people, get a surface temp thermometer and put an incandescent dimmer inline with the heating pad; this will allow you to get the temp
close to 30C but will not tightly regulate to that temp- it will change depending on the ambient temp. Allowing this temp to wander around will cause inconsistent results. You really should get a proper, thermostatically controlled horticultural heat mat.
I was wondering how often and how long I should run the drip. I have heard so many different things from watering 10 min. 24/7 all the way up to 1 hour once a day so what is your opinion on the matter.
Depends on the medium you're using. Pellets can be dripfed frequently if not constantly for large, mature plants. Absorbent media like RW can only be watered 1x/day for small plants (wk1-2 of flowering) or 2x/day for larger plants like well developed mums. I don't generally like drip systems because of their propensity to clog drippers, but watering from the top also means you will get a thick sludge of algae forming on the media tops as the top surface will always be wetted with nutrient soln and exposed to light.
I think your a bit advanced for me, i'll need to get an ec meter and start measuring nutes that way. Just heard i could get away without an ec pen thats all. Maybe after harvest ill grab one.
Sorry, but pH & EC metering are
really basic bits of kit for hydroponic growing- not advanced at all! Once you have been running your op for several months, you may indeed be able to get away without EC metering, but when you're just starting up, you really need all the information you can get.
I was wondering, shud i use the 11 plant or the ebb tray?
Use commercially made, moulded flood trays with drain channels. Systems with fixed numbers of sites and which prevent you from moving the plants around limit the utility of the system.
Al, I found my indoor to be near double the outside levels. Outside by me is about 400ppm indoor is about 700ppm. My grow closet, I leave the door open most of the time, hovers around 500-600ppm. Another reason to leave CO2 as the last piece of the puzzle.
Yep, that's kinda what I expected; people exhaling CO2 in the living space should reasonably be expected to increase CO2 concentration in the living space.
CO2 is a lovely thing to have, it's just bloody expensive to do it properly.
Got it what CFM fan would cool one 600 watt cool tube reflector?
A 150mm, ~200CFM axial should do just fine. That's what I have driving my 2x 1000W HPS in seriesed cooltubes.
I've been looking for the same nuts canna can't find them if you have the link would appriciate it.
Canna may be hard to get in the US. I can't offer you any suggestions as I'm not in Nth America.
Last question the person at the hydro store said I can flower in 4" or 5" square pots if the trays drains completly them no roots will come out is this true Al.
yes, that should be the way it works- works that way in my flood systems.
can I use rockwool instead of perlite?
yes, but you can't flood RW very often due to its high absorbency. Perlite permits more frequent flooding because it is less absorbent.