Rockwool issues

This is my first grow using rockwool cubes (3 x 3 x 2.5) and I’m having a problem that has never happened to me By that I mean when the roots grow through the bottom of the cube they turn a amber color as seen in the picture
I live in Tampa,Fl. and it has been getting really cold at night but I have a heater in the room where my
2 ft. x 4 ft. x 6 ft. tent is,
I’m am try to keep the room at 78 degrees so that is not so cold in the tent. The RH right now is between 50 and 60 % this is the middle of the 3rd week. What can I do, if anything to fix this issue

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You need fo get those cubes into dirt once you see the roots

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Air pruning because they are in a dry tray a layer of hydroton/lecca hydrocorn even aquarium gravel in bottom of tray with nutrient solution and the roots would stay white and healthy. Yes they are ready to be moved

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Thanks for that info, it’s my first time using rockwool cubes

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will it be ok for the roots to sit in the nutrient solution without any o2

It is a short term thing typically rockwool is intended for hydro applications can I ask how you intend to grow these ladies long term?
If you intend to use tray and just rockwool cubes like an ebb&flow system the flood and drain cycle usually provides some air as does an airstone and pump in res. If you plan to hand water them in that tray line the bottom as I stated and surround rockwool with medium light and dry air kill roots

I put them in square Tupperware contaners for now or should I put a thick layer of hydroton in the tray and watch the amount that I water them so not to much water will collect until I figure what is the best and most efficient way to grow them. Right now i am having an issue with keeping the RH between 50 and 60%, I just checked the Rh and it is 48% and the humidifier is on as high as it will go I live in Tampa,Fl. and it has been freezing cold lately and the humidifier in the 2 x 4 x 6 tent is not doing the job even though I have a heater in the room where my 2 x 4 x 6 tent is set to 78 degrees.
I still have 2 and a half weeks until I can move them into my 4 x 4 x 6 .bloom tent so I think I will leave them as is until I can figure out how I am going to grow them. I was thinking about RDWC. I have everything I need right now to build a 4 bucket system, but I have to wait unilt I harvest my current grow to set it up in the bloom tent

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I live in Northern BC Canada I think our opinions of cold would differ :wink:
That is a far better situation for you plants even as they are right now, you said you haven’t determined how you intend to grow them to completion yet? Starting in rock wool cubes as large as those I assumed you were doing some homework on hydroponic systems to choose which works best for you.
You still would have soil option at this stage too


My dad lives in Alberta, BC Before I came to Fl. I lived in Minn. for 5 yrs., that really sucked the big one. Yeah I did quite a bit of research on all the hydro systems on the market and saw a few videos on youtube and I liked what I saw with the RDWC (massive rootballs, huge plants) set up. I have 3 plants in soil right now close to harvest, after that I am leaning towards the next grow with RDWC. The last 3 or 4 days the temp in my veg. tent has been between 17c & 20c at night, will that stunt the growth of the plants ? They are at the end of the 3rd week and they are not very big

It won’t stunt them but may slow growth to some degree