Area51- rockwool grodan/Athena proline with Growlink controller

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Electrolights

Electrolights

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@rDWCNoob does the fully saturated rockwool after presoaking it take a while to dry by itself? I’m assuming since they’re so small their not drinking much I have the vpd dialed in, my sensor was at 90% wc originally I thought I had placed it in too low so I raised it a small bit and it’s been at 75% since last night figuring out if it’s my sensor, I guess the solution would be to weigh them as well
 
rDWCNoob

rDWCNoob

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If the plants aren't drinking yet, the block can hold water for days without really drying out much. But rockwool even fully saturated will hold something like 15% air at all times as well, even fully saturated. So in the beginning you're not really watering to feed the plant water or nutes, its not using much of either. You water to replace the air. As you water from top down, it sucks fresh o2 into the root zone. But because the plant isn't really drinking the blocks arent going to have much if any dryback. Weighing them is overkill. If youre worried about o2 in the root zone just water once or more a day. The plant will be fine, you cant over water it, at all. Its not like coco where its "almost impossible to over water" literally IS impossible to over water rockwool. You could water till runoff 5 times a day, every day, and the plant wont suffer at all when its still in veg.
 
Electrolights

Electrolights

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Well the one that was healthy realized it was drooping thought it was overwatering at first, then I checked the DLI was giving them waaay to much glad I caught it, brought it down to 25-30(added a second light in the tent) didn’t think anything of it until top leaves started lightening up and some of the new growth on one started to cup in
 
rDWCNoob

rDWCNoob

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Got any pics showing your progress? Would love to see how theyre doing. How long do you plan on vegging for?

Heres my current babies -

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My mums are getting a little old for those tiny little cubes and way too tall for my little veg tent, so i took some clones to replace them for my next run, which wont be till end of Feb.

Heres my current flower room -

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Much smaller than last run with only 3 days "veg" lol.
 
Electrolights

Electrolights

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@rDWCNoob so in theory if my rockwool ec itself is too high I can just keep feeding causing runoff till desired ec? Won’t post pics till they’re healthy lookin lol sitting at 2.0 right now even though I caused some runoff with .5 ec it’s steady 2.0 assuming some nutes from original soak are still hangin in
 
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Electrolights

Electrolights

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Also probably veg for 4 weeks unless they fill the canopy before that, just waiting on that to happen
 
Electrolights

Electrolights

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given it multiple 3% shots after field capacity at this point to drop ec below 2.0 but it won’t budge
 
rDWCNoob

rDWCNoob

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@rDWCNoob so in theory if my rockwool ec itself is too high I can just keep feeding causing runoff till desired ec? Won’t post pics till they’re healthy lookin lol sitting at 2.0 right now even though I caused some runoff with .5 ec it’s steady 2.0 assuming some nutes from original soak are still hangin in
generally speaking yes, you should be able to flush till the runoff is the same as the res. I wouldnt go too crazy though. I dont actually check my runoff ec, jusy my res. And I usually go off of PPM instead of ec. In veg I keep the res at 600-800ppm then 1000-1300ppm in flower. With how often you water, especially in veg, your root zone ec should be fairly stable because the rockwool is completely inert, it doesnt hold nutes at all.

In my experience flower is where things can get a little spicy in the root zone because youre allowing more dryback. If parts of the block get too dry you can get salt buildup in the cube, which i think is where you can see your ec spike with rockwool, but i dont have sensors and dont monitor it that way. What i do is look for tip burn and then increase my feed time/runoff to try to flush the cube a bit and maybe water down my nutes a bit, but not too much. You dont want to increase or decrease ec too drastically all at once as that will change the osmotic(?) pressure around the root cells and cause them to take up water too fast and burst. If you need to flush the block, do it with whatever feed strength you normally feed with and maybe water it down a bit. Dont flush the cube with just water mid cycle.

Again, its a completely inert medium so the plant generally gets exactly whats in your nutrient solution on every single feeding, which is one of the reasons its so great for crop steering. You can make even small changes to your feed and the plant will benefit from those changes very quickly. The caveat is that it will also react quickly to bad changes to your feed/res, although not to the same extreme as say rDWC. You wont see the same kind of swings unless perhaps youve got a recirculating res.
You can also flush the entire block at any time with just an extra long feeding, veg or flower, till you get the desired runoff. Just dont do it with anything too far off what youve been feeding, you want replace whats in the cube with whats in your res, which in theory, should be exactly the ec, ph and temp the plant needs.

Mostly you really shouldnt need to flush it at all unless theres a problem, ie. it dried out too much due to say a pump problem, which happened to me on my last run lol. However, its not necessarily a bad thing either. The 4 plants that got dried out the worst, looked the worst, had the most nutrient burn and also unfortunately were the smallest plants, had the absolute best smell and flavor by a long shot, although they were from a different mum as well, same strain. Ill find out on my current run, which is clones from all the same mum, if the added stress at the end really did increase the terps and flavor, which in theory it can and does.

With your sensors you should be able to dial the wc in and avoid most of that nonsense lol. You should just be able to keep your res within your desired levels and let it do its thing. So long as your nutrient solution is on point, and your pumps and sensors are all functioning, youre all set.
 
Electrolights

Electrolights

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So I ended up panicking with my ocd and found a way to dry them out because I weighed them and they were all close to the 3000gram range which is fairly close to the 108oz max volume of the cube, now they’re sitting at 50% starting the feed for the day and the two that are 1-2 weeks older are standing up and looking alright now, was totally water logging them from the original soak but I can’t figure out now why this sensor was just reading it was at 40% but a few hundred grams heavier than the two that are on the sides could just be that it’s a little younger so it’s taking more time to recover then overnight like the other two, I stacked the cubes on top of dry ones to pull the water out via gravity and it actually dropped them from 80% all the way down to 40-45 overnight, they’re on the clone trays because I felt they’re getting bad drainage since they were so water logged. What a damn learning curve
 
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rDWCNoob

rDWCNoob

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So I ended up panicking with my ocd and found a way to dry them out because I weighed them and they were all close to the 3000gram range which is fairly close to the 108oz max volume of the cube, now they’re sitting at 50% starting the feed for the day and the two that are 1-2 weeks older are standing up and looking alright now, was totally water logging them from the original soak but I can’t figure out now why this sensor was just reading it was at 40% but a few hundred grams heavier than the two that are on the sides could just be that it’s a little younger so it’s taking more time to recover then overnight like the other two, I stacked the cubes on top of dry ones to pull the water out via gravity and it actually dropped them from 80% all the way down to 40-45 overnight, they’re on the clone trays because I felt they’re getting bad drainage since they were so water logged. What a damn learning curve

Yes, stacking them will definitely drain the top one. Ive made that mistake when stacking a 4" cube on an 8" one. 8" just sucks the smaller one dry. Its because the rockwool acts as one solid cube, and the cubes have a water gradient, so the bottom is always wetter, while the top is drier.

Dont worry about over watering. The thing with over watering is that youre not giving the plant too much water, its too little O2. Like DWC, the roots can be completely submerged, so long as theres enough O2. The cool thing about rockwool as I said before, is that even when fully saturated, theres still around 15% air in the root zone. And, the way to give the plant more O2 in rockwool? Give it more water. It sounds counter intuitive, and if youve tried soil or coco, you need to unlearn some of the normal watering methods. Rockwool is different.

You can feed one of those 6 inch cubes, 2 litres of water, 5 times a day, and it will be perfectly fine. Every single time you water, once the runoff stops, your cube is at the perfect O2 level. It never geys any lower. If anything, not watering enough could cause the O2 to become depleted, not the other way around. Its the exact opposite of soil.

Looking at your plants it looks like youre still in seedling stage, but at this point theyve got some roots. So I think you could probably start watering with normal veg strength nutes or close to it. That should darken up your plants a bit and give it what it needs to enter full veg.
 
Electrolights

Electrolights

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Yes, stacking them will definitely drain the top one. Ive made that mistake when stacking a 4" cube on an 8" one. 8" just sucks the smaller one dry. Its because the rockwool acts as one solid cube, and the cubes have a water gradient, so the bottom is always wetter, while the top is drier.

Dont worry about over watering. The thing with over watering is that youre not giving the plant too much water, its too little O2. Like DWC, the roots can be completely submerged, so long as theres enough O2. The cool thing about rockwool as I said before, is that even when fully saturated, theres still around 15% air in the root zone. And, the way to give the plant more O2 in rockwool? Give it more water. It sounds counter intuitive, and if youve tried soil or coco, you need to unlearn some of the normal watering methods. Rockwool is different.

You can feed one of those 6 inch cubes, 2 litres of water, 5 times a day, and it will be perfectly fine. Every single time you water, once the runoff stops, your cube is at the perfect O2 level. It never geys any lower. If anything, not watering enough could cause the O2 to become depleted, not the other way around. Its the exact opposite of soil.

Looking at your plants it looks like youre still in seedling stage, but at this point theyve got some roots. So I think you could probably start watering with normal veg strength nutes or close to it. That should darken up your plants a bit and give it what it needs to enter full veg.
I have tip burn from 2.0 I’m down at 1.3-1.5
 
Electrolights

Electrolights

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Nice setup. What pump are you using in your rez?
Just something off Amazon in a 5g bucket got a 120 mesh on the end of line before the emitters had a cheap vivosun one before and didn’t think it was strong enough
 
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Electrolights

Electrolights

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Couldn’t stand using the photon phone dli app, had to scoop this turns out 23DLI on an apogee is like 32 on the app so the phone app is way off amped to have lighting on point on no longer wonder if the half ass phone app is fucking up the leaves or just eliminate it as a variable to troubleshooting, pretty fuckin penny for it though
 
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Electrolights

Electrolights

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Also just tested my sensor, reading 2.3 in a 2.77 calibrating solution and 90% wet fully submerged have to move settings around in crop steering hopefully they will send me a new one
 
Electrolights

Electrolights

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Quick update, definitely have everything on point now they’re getting ready to sleep finally got lights under control and they were praying all day roots popping out rockwool now left one still a little behind will probably top them this week, going to hydro store to pick up a 3ft slab to throw these girls on
 
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Electrolights

Electrolights

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@rDWCNoob ever used the grodan slabs? i just put the 3 of them ontop of the 6x36x6 slab and idk if i should be putting a drip stakes in or just let hte ones on the hugos drain into it
 
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