Greetings, New to this group and thought I would start a thread on my current grow and thoughts. And get some feedback. As stated in the Title this is going to be a grow using Ebb and Flow tables with Growstones in a Closed Grow Environment(CGE). The room is @ 12 x 12 and climate controlled. Presently the parameters are; temperature 74 degrees daytime, humidity 50%, CO2 1500 ppm. We're running 49 plants in a 8 x 4 and a 4x4 tray with a 100 gallon reservoir under 3 1000w HPS lights with space available for 3 more lights. We're using growstones for the medium. So far the biggest hurdle has been the growstones. They seem to take a lot of time and water to balance the PH. The plants basically look like shit because they suffered from high PH (nute lock?) for the first 4 weeks. I finally added an automated PH adjuster and at least the reservoir stays in the same place. After a flooding the tables with 5.7 PH adjusted water and nutes the water running back out of the pots is in the 7 range. It's better than it was but still too high. The next time the plan is to soak and rinse the stones multiple times to see if they can be better balanced before starting. From this sad starting point it's been catch up. After adding the automatic PH adjuster the plants have taking off, growing 1 to 1 1/2 inches a day. I'm now starting the process of optimising the nutrients level. The PPM's in the reservoir have dropped every 24 period. There has been severe yellowing and other ugly leaf issues. I'm hoping this is the lack of nutrients and not other problems cause by the PH debacle. Thoughts?
Oh dear me! I'm too just to about to start my first hydro (ebb n flood), and reading this I'm now worried as Im pretty sure can't afford a ph adjuster. What brand of clay pebbles u using Plz? I'm sorry im not be in helpfull 😉
I don't think clay pellets have the same issue. I'm using Growstones. They are more durable and the plan is to sterilize them and reuse them.
What are these grow stones made of? I reuse clay pellets for years. I never have any issues with pH or durability? You say your nutrient PPM was dropping, that would cause the pH to go up some. Are you topping off the res with straight water or a nutrient mix? Do you flood the tables in parallel (a separate flood/drain line to each table), or in series (from one table to the next table to the next table)? Don't worry about using clay pellets. With a good nutrient regimen, you can keep the pH within a good range for a week at a time or more (depending on reservoir size).
Thanks for this I've got my head around ppm now with a single bucket before i run whole hydro set ups and a cheap ph pen on way here tomoz 😊
http://www.growstone.com/ They are made of recycled glass. I want to figure them out because they are a bit more eco friendly. The PH has been going up dramatically, up to a full point, 5.8 to 7. How many times can you reuse the clay?
As many as u want, use some liquid oxygen ( hydrogen perxiode) to clean them. At least that's what I do
Personally, I don't think it's the grow rocks causing the pH to shoot up (you could test by putting some in a bowl of water and see if the pH shifts over time). The only thing I've seen to cause pH to shoot up like that is water born pathogens in the system. Do you have a thin layer of funky looking stuff floating on top of your reservoirs? The only time I've had pathogens in E&F is when I had a fill/drain hose get clogged and the table was taking way too long to drain. It caused pH to shoot up very quickly. The plants in the picture look like the roots are suffering from lack of oxygen. They are droopy and unhappy looking. Do you have rockwool cubes buried in the grow rocks? How long to you flood during the flood cycle? How long does it take for the tables to drain? I used to have 2 tables exactly like those, and if you don't cover them you're going to have huge algae blooms soon.
Thanks for the replies. We're not having an algae problem yet. The reservoir temp. has been at 68 and I'm installing a water chiller tomorrow to drop it to 65. We're also running Hydroguard. Also running an Airforce air pump with airstone. As for the stones we have been checking them along the way by pulling the pots out and draining into them and measuring the ph there. And it's almost a point higher than the flood water. We've also checked new stones with the same result. Thought about the rockwool cubes, but they are so small and above the flood level I don't see how they could account for the raise. Ultimately going directly from the Aerocloner to the tables and into bud is the plan. Wondering if anyone has done this? The flood and drain times are 8-10 mins each. The plants have been growing 1 1/2 to 2 inches a day. I think we're getting out of the woods but are still suffering the effect of the high ph in the beginning. Also the return ppm's have been 100 points lower than the reservoir. 940 down to 840. This seems to say the plants are doing much better and using lots of nutes. Sounds about right? Skipped the 2nd week of the House and Garden 8 week because the ppm's were dropping so much. Seems to be evening out now. Will post new pics on Monday.
There is certainly damage remaining from the previous problems. But it seems that the new growth is vigorous and healthy. Ended up with SOG on the 4 x 4 table at around 1 per square foot. The other is more of a ScrOG setup, with all of the various branches spread out as easily as possible. Even with 9 foot ceilings it seems that it will be a tight fit by the end. Impossible without the screen. The hope on the SOG is that there will be no need for a screen. Most of the plants are 12" or less. They are very tightly packed for their size. They may need to be spread out again. Running the 3rd week schedule of nutrients twice as the ppm's are rising slightly when the reservoir drops. There was a problem with the AC that it was turning off or down in the middle of the cycle. Temperatures would spike has high as 90. The CO2 really saved the plants from any damage I believe. One should have an emergency air intake and exhaust set up in case of AC failure. Eventually. There was a question earlier about the possibility of algae buildup. Still no buildup but on the cloth pots. They are the first thing I will change next time. The get wet and stay wet. They are now slimy up as high as the flood level. This can't be good although there are not any options in changing pots at this point. Try plastic next. This is the first major change so far.
There's been a good recovery so far. Wondering if we should have supplemented cal-mag in the well water? Bought an ec calibration solution today to see if the well water has any thing in it. I thought we measured it and it was 100 ppm but when I checked it last week it read 0. I think it must of been calibrated in the well water. Going to add some in the reservoir this next weeks cycle. A half dose. See what happens.There is certainly some funky leaf stuff that happened that looks like mag deficiency. And while most of the color is come back to the leaves they could have used a little extra nitrogen, which cal mag is full of. The Ideal Aire AC is acting up. It will not hold the temperature we set. In 3 weeks it worked perfectly for about 6 hours, last night. Spent tons of time dealing with the techs but they were not very helpful. We have reached the agreement that it's the motherboard so to their credit they did send a new one. Again we'll see. Starting the 5th week tomorrow. Following House and Garden regime and because of dropping ppm's in the reservoir have boosted it to the next weeks dose a few times. I don't see any burn on the leaves and most of the damage is on older leaves now, which is a good sign. I would consider the buds at this point to be slightly underdeveloped and not as crystally as they could be but they're not the worst I've seen either. No doubt the CO2 and hydroponic system helped in that regard. Set up an emergency exhaust fan. The temperature sit at 84 sometimes because of the glitch AC. They see to be hanging in there even with the wild temperature swings.The plants closest to the AC get blasted the worst and don't seem any worse off than the others. Interesting note: My partner didn't turn the light timer back on after checking the settings so the plants had a 36 hour light period. They had no problem with that. Some people grow with 24-36 hr light periods so I figured the best thing was to leave the lights on instead of having a shorter dark period. I've seen a shorter dark period really fuck up plants.
A week 7 update. We've had a number of other issues but somehow the plants look as if they will produce something. How much is yet to be seen. After multiple double checks it seems our well water is 0 ppms. We've been operating as if it's been at 100 ppms. I remember checking the ppms at the start and it reading a 100. The meter must not have been calibrated. The big issue is the cal/mag that I thought I was getting and I wasn't. Since this was discovered in week 4 it was a little late to add it in. I decided to add a half dose of Cal/i/mag/ic. The plants responded fine, no burning. Cal/i/magic/ic is high in N so was very careful with it. When the week 5 reservoir was mixed there was a miscommunication and a full dose was mixed in. Burned the hell out of the plants. Easily seen in the pictures. There are Cal/Mag additives that do not have such a high level of N but pushing the plants as we do I'll probably keep using this kind. Two other major screw ups also came to light. First off I noticed we were getting what looked like a K deficiency, dry edges, turned down tips. I went to the store and checked out one of the House and Garden additives we haven't been using, Multi Zen. It was mostly K. When I asked them about it they said this was a must have part of the system. Another miscommunication as they had said I didn't need at the start. I didn't add it as it was the start of week 7. In the middle of the House and Garden discussion the clerk said he had had a long conversation with H&G about using an airstone and they said not to use one in the reservoir because it oxidized the nutrients. Just use a circulating pump. Another major misinformation. So far the grow store I used gets a D grade on their knowledge and help. Luckily there was a knowledgeable person in the store that was able to sort through the problems. It's hard to believe that the plants survived all of the issues!! Another major issue of note is the Ideal Air AC. It's never worked properly, often allowing our temperatures to spike, sometimes as high as 92. We finally switched it out with a new one and the problem, whatever it was, is solved. Looks like a couple of them are nearing done but the majority are still a couple weeks away.
Here's the link to staggered crop in the same room http://forum.grasscity.com/indoor-medical-marijuana-growing/1365594-vegetative-growth-aero-cloner.html
Instead of starting a new grow journal I'll treat the room as one continuous grow. To follow up on the last post, talked to House and Garden and although it was true a few years ago that using an airstone would oxidize the nutrients they have changed the formula and that is no longer the case. At this time one reservoir on an air stone and the other on a circulating pump. We'll see if there is a difference. A couple of days ago looked at some of the plants with a loupe and could see no cloudy trichomes. One of the problems with running a number of strains on the same table is they are going to get done at different times. Start of week 8 Friday. The other half of the room is now full and running smoothly. For the first time all 6 lights are on. The AC is letting the temperatures climb a little but within reason. @79-80 tops. To fill in the missing info; 48 clones fully rooted in 12 days. Dropped the lights to right above the canopy, added nutes and vegged in the cloner for another 10 days. Put into bud with the majority of plants in the 10" range. After 2 weeks went in and trimmed off all lower branches and lower growth. Spread the plants out to 1 per square foot and turned on the last light. Now in bud under 3 1000w DE HPS.