Dookie69 Posted August 8, 2021 Share Posted August 8, 2021 The coco/perlite media in my autopots tends to dry up at the top because the system wicks from the bottom.It was suggested that I use a layer of perlite on top to help retain moisture in the upper layer of coco. The issue with that is since it is so light, it might sort of float away if I need to do a top flush. Whatever I use it can’t be organic, and since I don’t use the media twice, it doesn’t matter if it gets mixed with the coco over time.Has anyone tried fish tank gravel? I refer to the whitish quartz type gravel which has a diameter of 1-2mm.It’s also been suggested to use clay balls (hydraton?) Another idea is a plastic square with a cut-out for the main stem. This worries me a bit as it might not breathe as well as a gravel would.Any suggestions?thanks Quote Link to comment Share on other sites More sharing options...
The_StonedTrooper Posted August 8, 2021 Share Posted August 8, 2021 I could be wrong, but Perlite is organic You can definitely do that on top, and I have done so to prevent gnats and drying out. After a few days or so, the perlite compacts and it wont go anywhere. You'll be fine with that, and it will make a huge difference 1 1 Quote Link to comment Share on other sites More sharing options...
GGG Posted August 8, 2021 Share Posted August 8, 2021 Perlite also floats to the top so you will be fine as mentioned above.If you do have the airstone domes at the bottom I would assume that the air will anyway go/pump upwards and no need to worrie if you want to do a cut out , maybe make the stem cut out not to small and tight and leave a 2-3 cm open around the stemSent from my Hisense Infinity H50 using Tapatalk 1 1 Quote Link to comment Share on other sites More sharing options...
Marzcanna Posted August 8, 2021 Share Posted August 8, 2021 Add perlite to the top, thats exactly what I did with my organics in autopots. 2 Quote Link to comment Share on other sites More sharing options...
Batista Posted August 10, 2021 Share Posted August 10, 2021 Hydroton will be perfect if you can get it. It won't move at all, and is inert. I use this on the top of my dwc buckets, allows air exchange and allows me to top up through it.With perlite it will move around, push its way deeper and you will need to add more to maintain it. Sent from my SM-A715F using Tapatalk 1 Quote Link to comment Share on other sites More sharing options...
PsyCLown Posted August 10, 2021 Share Posted August 10, 2021 Why do you not want something organic? Perlite could work, hydroton as well and I think that quarts gravel stuff would work well too. Hydroton I think may be easiest as it wont get washed away or worked into the coco as much as the perlite. 1 Quote Link to comment Share on other sites More sharing options...
CreX Posted August 10, 2021 Share Posted August 10, 2021 Not sure what the initial issue is? Pot drying out from the top sounds normal. Hydroton would work best I guess and it's cheap. Maybe water more often? Quote Link to comment Share on other sites More sharing options...
Naughty.Psychonaut Posted August 11, 2021 Share Posted August 11, 2021 what's goood @Dookie69 was watching a cannacribs youtube video last night, got these two screen grabs for you check the video out. there's two different times they discuss the covering of the top of the grow medium. click on the link that takes you to youtube. 1 Quote Link to comment Share on other sites More sharing options...
Dookie69 Posted August 11, 2021 Author Share Posted August 11, 2021 Not sure what the initial issue is? Pot drying out from the top sounds normal. Hydroton would work best I guess and it's cheap. Maybe water more often? I can’t influence the watering, it’s a self regulating bottom feed wicking system. The top third of coco is bone dry, I think having the moisture wick higher in the pot will allow more root development. Quote Link to comment Share on other sites More sharing options...
Naughty.Psychonaut Posted August 12, 2021 Share Posted August 12, 2021 I don't think covering the top is our answer here, because it's not your lights or airflow that's causing the drying of the top medium, but rather a poor wicking if I am understanding correctly? It was our good man @CreX who made a short threada while ago regarding this Key words are "capilary action" maybe give this a looksee? you could research more, but it's a good starting point, because that seems to be where your problem lies. maybe look into adding some peatmoss or good quality coco to your medium? 2 1 Quote Link to comment Share on other sites More sharing options...
PsyCLown Posted August 12, 2021 Share Posted August 12, 2021 7 hours ago, Naughty.Psychonaut said: I don't think covering the top is our answer here, because it's not your lights or airflow that's causing the drying of the top medium, but rather a poor wicking if I am understanding correctly? It was our good man @CreX who made a short threada while ago regarding this Key words are "capilary action" maybe give this a looksee? you could research more, but it's a good starting point, because that seems to be where your problem lies. maybe look into adding some peatmoss or good quality coco to your medium? This is true, might be worth while playing with the coco / perlite ratio. Not sure though. 2 Quote Link to comment Share on other sites More sharing options...
Dookie69 Posted August 13, 2021 Author Share Posted August 13, 2021 I use Freedom Farms F1 as it comes out the bag. I’m might be wrong but I think the substrate is ok.The plants seem happy with the F1. I have layered the clay pebbles and coco correctly according to Autopot instructions. I have a bag of perlite now, will try it out to see if it helps or not. I’ll also try checking the damp coco level in a late veg pot, maybe the thirsty plant pulls moisture up high as opposed to a harvest- ready mature plant. Quote Link to comment Share on other sites More sharing options...
Naughty.Psychonaut Posted August 13, 2021 Share Posted August 13, 2021 how was the moisture in the pot with the younger plant? do you only have the issue of the top layer being bone dry with the mature harvest ready plants? if this is the case then it's perfectly normal. pots are same size one with more root mass will mean more water uptake which will cause the water/moisture to never move all the way up to the top of the pot. capilary action will be effected. where as a young plant with less roots will take longer to suck the medium dry and your capilary action will be closer to normal. I would say if you wanted to test the capilary capabilities of your medium, rig a autopot with nothing but medium in it and see what you get? other than that, if you say the F1 medium is right as is and you followed autopot instructions then maybe contact autopot people and tell them you done everything right and there's a design flaw in their product 1 Quote Link to comment Share on other sites More sharing options...
Dookie69 Posted August 13, 2021 Author Share Posted August 13, 2021 This is a side view of the F1 pulled out of the pot. It was harvested and left in the pot for around 3 or 4 days so it probably dried a bit more in that time before I pulled it out to inspect. 3 Quote Link to comment Share on other sites More sharing options...
PsyCLown Posted August 14, 2021 Share Posted August 14, 2021 I don't think it's that much of an issue.They have constant water at the bottom like a plant in hydro and fresh air via airstones?Just a portion at the top which doesn't have any roots which dries out.I don't think adding mulch at the top would help much either as I think it's more of a wicking issue. It might make a small difference, doubt that difference will be worth it though and don't think you'll notice a difference with the plants either. Sent from my Redmi Note 7 Pro using Tapatalk 2 Quote Link to comment Share on other sites More sharing options...
Dookie69 Posted August 14, 2021 Author Share Posted August 14, 2021 The roots completely cram into the air dome space. I don’t suppose there is much root activity at the top. 1 Quote Link to comment Share on other sites More sharing options...
PsyCLown Posted August 15, 2021 Share Posted August 15, 2021 I assume there is constantly water with nutes covering those roots as well, so a lot like a hydro grow.There are barely any roots at the top of the medium even where it does wick up. Sent from my Redmi Note 7 Pro using Tapatalk 1 Quote Link to comment Share on other sites More sharing options...
Dookie69 Posted August 15, 2021 Author Share Posted August 15, 2021 Yes it is a bit like DWC with that aerated root ball. I think the top layer being dry must “air-prune” or discourage root development there. I’m wondering IF the wicking goes all the way up, would there be roots in that layer, and if there were, would they be significantly useful to the plant.I’m also wondering if having dry coco is in any way detrimental to the lower layers of moist coco especially in terms of Calcium demand… Quote Link to comment Share on other sites More sharing options...
Batista Posted August 16, 2021 Share Posted August 16, 2021 Yes it is a bit like DWC with that aerated root ball. I think the top layer being dry must “air-prune” or discourage root development there. I’m wondering IF the wicking goes all the way up, would there be roots in that layer, and if there were, would they be significantly useful to the plant.I’m also wondering if having dry coco is in any way detrimental to the lower layers of moist coco especially in terms of Calcium demand…Are the plants showing any signs of being stressed? I have done grows before like this and allowed the top to dry with no real issues. Visually is looks terrible because coco should never be allowed to completely dry out if you are using synthetic nutes but I wouldn't worry too much. Those autopot systems work well when you get everything dialed in. Sent from my SM-A715F using Tapatalk Quote Link to comment Share on other sites More sharing options...
Dookie69 Posted August 17, 2021 Author Share Posted August 17, 2021 No the plants are good, I think. Always room for improvement though. 1 Quote Link to comment Share on other sites More sharing options...
Batista Posted September 3, 2021 Share Posted September 3, 2021 I would try to pull some roots out the air stone, if it doesn't come out easily then don't rip it, but i find I can remove 10% root mass in dwc with no issues. Sent from my SM-A715F using Tapatalk Quote Link to comment Share on other sites More sharing options...
Dookie69 Posted September 3, 2021 Author Share Posted September 3, 2021 The roots can’t be accessed without pulling the whole plant and coco out the pot. So not a good idea with auto’s.Besides, I do t think the root mass is a problem, auto’s only run for a max of 3 months so it doesn’t get much worse than that. 1 Quote Link to comment Share on other sites More sharing options...
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