Backyard Aquaponics
A place to discuss aquaponics

Hey everyone, so.. i've been playing around with nft dwc and even the gromedia but i've seem to always stumble upon the same problem so far. My plants are not developing a root system(like i see in the guides on youtube) and i presume they are bolting. And a newer problem is the green algae that's developing.

In all honesty i must say that up untill 2 weeks ago i've been using an improvised led i've made and just recently one of 45w i've ordered from china has arrived and is working perfectly i wanna believe.

I am highly confused as to why my plants are developing nicely up untill a certain point and untill last night they were normal and this morning i've woke up to find them all what i can only assume as bolted and cupped twords down.

I would also like to mention that for nft or dwc i have been using my fish water only and no other additions like others use. I would like to just grow a salad from A to B. I've been monitoring the temp. pretty regularly in order to not have it bolted and it oscilated between 24-29 Celsius with the new led system i've bought. And my initial seedlings which are in the pictures i will attach at google drive, were put at:

some at 26cm distance from the led and others at 21cm.
On average the led is working between 12-14hrs a day

Now that i've woken up 11.08.2020 they are all what i can only assume as bolted, greene watered:d and cupped downwards(which only happened instantly and in the dark)

Links:
https://drive.google.com/file/d/1FZsPbU ... sp=sharing -green water bolted and cupped

https://drive.google.com/file/d/18j-YBr ... sp=sharing - same

https://drive.google.com/file/d/10XA5KF ... sp=sharing - before bolting under led seedlings(probably around 05.08.2020 at the time i took that pic

https://drive.google.com/file/d/1hamAtI ... sp=sharing - today 08.11.2020

500 views and no answer?teh..

I guess part of the issue with no reply is an inability to see an actual problem with cupping. I can see that the outer leaves in some photos turn down at the tips but this is actually fairly normal for some kinds of lettuce. The algae is there because much of the water is exposed to light and there are nutrients in the water - put those two things together and you're almost certain to get algal growth. I notice you also have some duckweed. Both the algae and the duckweed will take nutrients the plants could have used. If you want to limit the algae growth you need to cover any water that is exposed to light.

The other thing that is confusing is the use of the term bolting. Bolting refers to lettuce that has gone or is starting to go to seed. Your lettuce doesn't look to me like it has. The temps you're working at are a bit high and could encourage bolting of lettuce (above 21C) as it gets older but there are varieties that are resistant to bolting at higher temps if you look for them. It also helps to start lettuce seedlings at lower temps (consistently below 10 degrees C) - they bolt later (both these bits of information were picked up off the web from https://harvesttotable.com/lettuce-bolting/ but there are plenty of other sources for similar information).

So my recommendations would be to block the light to stop algae growth and look for a variety of lettuce that is resistant to bolting since you are working with fairly high temps for lettuce growing.