got a slight problem with my vertical grow.

Have a look at this image.

Each bulb has 8 tubes with 3 plants per tube. 2 tubes per reservoir cos I'm doing perpetual harvest. Been a bit of a struggle keep up with demand from my veg chamber but I'm slowly getting them bigger and bigger. Should achieve optimal in a month or 2.

Anyhow for some reason the plants at the top are wilting then the middle ones slightly also but all the bottom plants are healthy!?!?

Cant figure out why. It's not heat cos the top one are all the worst and the hottest point is the middle. Beside I'm using 8" cool tubes and an 10" isomax fan so temps are perfect.

The only thing I can think is that the drip system is saturating the rock wall cubes too much. With the top rockwall cubes of each tube being the worst effected.

OR

Salt build up at the top. Perhaps I need to flush out now and then?

What do you guys reckon?

The tops are droopy due to no light reaching them. If you were to put an overhead hid they would perk up in 2 days, or raise the vertical.

You reckon? I don't think so!

That's a 600 watt metal halide and it's bang in the middle although it doesn't look like it. If what you think is right then the bottom plants would droop as well. Also it's the tops that droop the most and some drooping on the middle ones too with the bottoms looking the healthiest.

The middle ones get the most light but the pattern goes after about 2 weeks into 12/12 tops start drooping and thinning leaves and get worse, followed by middle but so far no sign of any issues on bottom plants.

can't figure it!

Maybe it's something to do with saturation. I'm using mapito and running a fast flowing drip system for 15 mins x1 hourly. I've recently switched to 15mins every 3 hrs cos this mapito holds water well.

I've actually got passable results hand watering these tubes every other day with mapito. Results weren't great but quality was spot on and plants were small but very healthy. Perhaps I should switch my timer to every 12 hrs only or even x1 every 24 hrs.

It could be insufficient veggin time. I only have my plants in the tubes for 10 days prior to going into the flowering room. Perhaps rockwall cubes are saturating due to not prolific enough root growth splitting them open enough to handle the fast trickle of nutes they are getting.

Fuck, I don't know

Yep, I'm sure of it now. It's over watering.

My theory is the rockwall cubes are getting saturated too regularly. The reason the bottom one is doing best is because root systems are dropping down and taking away the water faster. That's why it goes from good to bad from bottom too top. The higher the rockwall cube the less roots from above to remove some of the water.

Bump - I'm not that sure!?

Sounds to me your on the right track. Mapito does retain a lot of water. It wont hurt to let them dry out for a good day. They will be fine probably even for two depending on how much medium their sitting in.

I flood 4 times a day for 15 mins and Im in coco and a flood table. I bet you would be fine 4 times a day too. Or if you want more feeding's cut down on the time spent on. like 15 secs every 15mins if thats what you want. Have to experiment and feel that mapito during lights on.

Yeah looks like simple overwatering- that rockwool will hold a lot of moisture. Maybe try putting the drip pump on a timer. Had a similar issue w/ my aero sprayers- had to allow more air to the roots by setting the sprayers to go off less frequently

roots want oxygen and a cool dark place. just remember the basics and fundamentals will help you get a long way.

Too little water is always easy to diagnose. Too much water can appear as various things, which can mess up your troubleshooting thinking. But it is easy to back off the amount for a few days to test.

Cheers guys. I'm still battling it and it seems to be getting worse.

I'll post some more pics to see if it helps diagnosis.

View attachment 30009806" tubes from the rear

Honestly it looks to me like there is a lot of mapito there and its getting soaked towards the top. While the bottom is getting a trickle which is the perfect amount it seems.

I would say the way that system looks it needs some type of other airy medium in there so help air flow. I would suggest the large grow stones mixed in with the mapito would help you maintain a proper 02, water balance.

I don't think so. I have been recently manually flicking on the pumps for about 4 or 5 mins which equals about 2/3 litres per tube every 12 hrs and they feel dry and airy at the top if you stick your finger in. I'm starting to think it's salt build up. I'm not really flushing ever cos my levels are so low (ec1.2) I figured I'd get away with x1 monthly or something but I think I may have to manually flush once a week.

I'm not sure but.... I think it's effecting the tops and middles lesser so cos nutes are running through and depositing salts along the way which is building but by the time it gets to the bottom it's being ate up and the plants are healthier down there too so they use them up faster as well.

I'm thinking of adding H&G drip clean when it arrives on thursday and in the meantime to a fair bit of manual flushing. Grr this is annoying

Sounds like your onto something. That mapito probably does retain a lot of salts.

Does your system just drain to waste ?

I just want to add on my point that the top layer would be dry because it see's air. Then again I don't know how far those tubes go in either.

I do personally flush my system and my plants for 24 hrs with tap or clearex before I re fill and feed.

Cheers man.

It's a recirculating system. For every x 2 tubes I have x1 90 litre res. Usually with about 40 liters filled. So when the second rig is loaded I'll have 16 tubes x 8 reservoirs with every pair of 2 tubes 10 days ahead of it's neighbour. When 2 come out, 2 go in.

I soak the mapito for 24 hrs before reusing it and run the system also for a few hours continuously draining and adding tap water until salts go down. Then I add RO water and nutres and put it into the system.

BTW the tubes don't sit in nutrient. They are sat on a board that has holes in it so they drip about 10" down into reservoir.

Here's a pic of a bare tube before being loaded and sealed. The bottom peice of timber gives it stability when it sits on top of the board that is on top of the res. I made it so every tube is easily detachable at any stage. It also allows me to mount reflective sheeting.