Slow growing seedlings

C=Answer if you grow coco ----Coc




E-indoor or outdoor indoor
E-soil, soilless, coco, aero, or hydroponic Coco
E-specific medium Canna bag coco

SCL-Anything you added to the soil. Started with 75%ro 25% tap started adding B1 drop of superthrive and today weak mix of canna coco nuites
SCLR-Soil or slab runoff pH 6ish according to color code
E-Water source tap/ro mix
E-Source water pH 6ish

E-Age of plant 2 weeks
E-Type of fertilizer ph'd water for the first 10 days .B1,superthrive,coco nuites
E-Rate of application (if hydro, this is your PPM number, preferably after each component is added) Watering every 2 to 3 days
E-Lighting source and distance from plant 400watt metal hydride. 2 feet from plants
E-Air temperature (both day and night if you are running a dark period) temps are between 70 to 82 depending on time of day. normally runs around 75 degrees
E-Air % Relative humidity 30 - 40%
E-Lighting schedule 24hrs
E-Type of ventilation your room has 10" fan on plants. 6" inline exhaust fan
TR-Did you pre-soak your media in pH corrected solution? yes


The seedlings are growing at a snails pace they are looking really jagged. one of the seedlings is drooping. They are a light green color. No spots or yellowing. Using GH liquid testing kit. I call the water good when it is yellow to yellow-orange. I have to mix the tap with ro water because tap water is reading 500 ppm according to my truncheon.

Can you get pics up?
Also, and this is important and I'm sure you know this- do you have any idea where the high ppm of your tap water is coming from? You're TOTALLY correct to dilute it down with RO but I'm wondering if the tap water has high mineral content, or if the ppm is from another source. The fact that it comes in at pH 6 worries me, because a lot of CaCO3 would actually have it coming in at 7.0 or even higher. I ask because you could be seeign calcium problems.
If you already run an RO unit, I'd strongly recommend skipping the tap water since it is a big unknown, and making water that is RO+ calmag up to 250 ppm, and then adding your canna coco ferts JUST before your feedings, and give them at ~6.4. WEAK, because your plants are young.
Also very important: How much B1 and Superthrive are you using? That stuff can put your plants in a damn coma. Yes I have killed my fair share, and then some, of seedlings with ST alone; you add ANOTHER hormone into the mix and you get trouble!

Post pics
Lose ST and B1
Run RO+calmag to 250 ppm in place of tap water
Give light feedings appropriate to life stage- 1/4 strength nutes when the plants have 4-5 nodes, working up gradually.

Good luck

The ph of the tap is around 7.0. The ph of the RO is 6.0. The tap water is high in calcium according to the deposits it leaves on faucets. I'm not sure what else is in there though. Its municipal water for what thats worth. I used 1 drop of the superthrive and 1 teaspoon of B1. The canna nutrients I used 4ml/gal. I've only used the canna nutrients once and now both plants are drooping. Getting the water/nutrient mix down is going to be a bigger pain then I had though. One of the seedlings is starting to twist a little. you can see it in one of the pictures. I'm getting The RO water from a machine. I can't afford my own right now so I'd like to be able to use the tap/RO water if it will work. I will cease using the superthrive/B1. Thanks for taking the time to help Stinky, your the best ;). These seedlings have just reached the 2 week old mark.

Hi All !!!! :thumbsup:

justsoso they look pretty good!!!!

I had some Thai seedlings that just wouldn't grow, after about a month
they took off and are really healthy.

I suggest patience they look gooood!!

justsoso i am recovering from a few weeks of very slow seedling growth in Canna coco. I have been researching for a while and have heard a lot of differing advice.
first of all STINKY IS THE BOMB. So obviously read closely what she types, i know i do.
I was told that canna coco should be flushed with calmag if it is fresh out of the bag. It is loaded with K and adding flushing with calmag will supposedly replace some of the K with calmag.
I have just today switched to RO water because my girls + boys were getting water from a new source i was unsure about (220ppmtap).
Also i had better luck when i let the coco dry out a bit so the roots would search for water and grow. That helped some.
I feed botanicare and am at 7.5ml grow and 5ml of calmag/ Gallon with r/o.
They have continued to look like they are not getting enough Nitrogen, and i wonder if the extra K in the canna can lock out Nitrogen? I know someone who probably knows the answer...coughstinkycough...?

Just some nute for thought!:jointsmile:

should be fine..

small plants grow lower... simple reasoning, smaller the plant, the less light it can absorb.. as it gets larger it perpertually grows faster.

Don't even pay any attention to the pH of RO water. It is meaningless. Read the chemistry link in my siggy.

Those seedlings look great by the way! If it ain't broke... ;)

Thanks for the guidance all. The drooping was a ph problem. I had to lower it from 8 down to 6. A couple hours after doing so the drooping was gone. As far as being high in K, I'm not sure about that one. I haven't read from the coco logs of people having issues with that. If I were having yellowing issues, I would flush, then restart my feeding schedule. The coco dries really fast once the top is dry. The plants are starting to come around. Growth has been more in the last couple of days then the entire last 2 weeks. Now my problem is going to be temps. I'm really trying to keep from running a heater, thats why I've been using the halide bulb instead of flouros, but I'm not sure its going to be able to keep up. Temps are running in the lower 70's now. With RO water having a low ionic strength, how do I determine what my PH actually is? Does it take the ph of the tap water when I add it? When I add ph down, it rockets down to a ph around 4. This is using less then a 1/8 tsp of down. Stinky if you read this one, good luck with your interview, I've got my fingers crossed for ya.

Forgot to ask, If I want to setup a drip system once my plants get a little older, how do I go about adding the nutes? How long will my nutes last in the res before I start having problems with them? I'm assuming the nutes are designed for a hydro style setup?.

I've got these spots on 2 sets of leaves. Some of the spots are yellow instead of brown but I have a feeling they'll be brown soon. Ph run off is 6ish. Lightly feeding with the canna nutes, 5ml/gal. ST and B1 are no longer being used.

My above mentioned plants are doing real well now. I was seeing some of the same colors you are. The pale yellow-green foliage and some spots on the lower leaves. The solution to my problem was to actually increase the feeding. Mine are a little smaller than yours and already getting a combined 800+ ppms of Botanicare products.
I am not an expert, but after hesitating in increasing my feed for weeks, i finally did it and things are happy.
It may be that the "light feed" of nutes is not enough. Try increasing it on one and if they are in fact just hungry then you should see it within a day.
I am only sharing my experience, and could be totally wrong...but maybe not:jointsmile:

Ive upped the nutes but problem is continuing. Its moving up into the new growth.

Your runoff is WAY too low. You should be aiming for 6.7 runoff. Also, you shoud be running calmag on 'drinking' or RO water. Get the ppm up to 250 before adding nutes, THEN add nutes, THEN check and adjust the pH. Once the nutes are in solution, the pH is testable and matters.
Thanks for the wishes! I think it went GREAT and I expect and offer!

Hey Stinky. I see you said to aim for 6.7 ph runoff in Coco. I was under the impression that 5.8-6.5 was correct since Coco is closer to hydro than soil. You know lots more bout this than I do but I want to make sure I read this post right before I make any wrong changes. thanks.