Seedling problems, over/under fed??

[Rob547]

I always have problems with seedlings, I dunno what I'm doing wrong. Have started them in new soil and before that jiffy cubes (not these but the ones I just planted) anyway...

SOIL:

How long has this problem been going on? Few days
What STRAIN are you growing? unknown bagseed
What was the establishing technique? (seed or clone?) Seed
What is the age of your plants? About 3 weeks
How Tall are the plants? Short, 3-5"
What PHASE (seedling, vegetative or flower) are the plants in? veg
What Technique are you using? (SOG, SCROG etc) SOG
What size pots are you using? (Include how many subjects to pot) 1 per 12 oz solo cup
What substrate/medium are you using? What brand of soil mixture are you using?(percentage of perlite, vermiculite...etc?) MG cactus soil (i know..)
What Nutrient's are you using?How much of each with how much water? How Often? *Knowing the brand is very helpful* none
What is the TDS/EC/PPM of your nutrients used?
What is the pH of the "RUN-OFF"? not checked yet, just above 7 (7.1) non-run-off
What method of pH test was administered? Using Strips? pH pen? indicator solution
How often are you watering? Relatively often, every 3 days or so
When was your last feeding and how often are you feeding? none
What size bulb are you using? 4 40w t12 + 3 23w CFLs
What is the distance to the canopy? Very close, an inch or so
What is your RH Factor? (Relative Humidity) almost always 16%
What is the canopy temperature? Almost always between 72-76 F
What is the Day/Night Temp? (Include fluctuation range) not much range
What is the current Air Flow? (cfm etc.) One fan blowing on them
Is the fan blowing directly at plants? Yes
Is the grow substrate constantly wet or moist? Dries out quickly but not constantly either
Is your water HARD or SOFT? hard
What water are you using? Reverse Osmosis (RO)? Tap? Bottled? Well water? Distilled? Mineral Water? Bottled water for seedlings, tap water left out for 24 hrs for rest
Has plant been recently pruned, cloned or pinched? nope
Have any pest chemicals been used? If so what and when? no
Are plant's infected with pest's? no

All the info is for the first plant, the most affected. I flushed it maybe 5 days ago, it really picked up and even grew a little over the next 12 hrs but then went back to sucking. The other one is the same but was given 5-1-1 once a couple days ago (fish emulsion) 1/2 strength I believe. Almost all have yellowing bottom leaves and/or brown leaf tips at the bottom. Also the first pic, it is dry and crumbly to the touch, not any closer to the lights or anything though. ph problem?? I'll check the runoff as well once I get a chance. The MG soil is .12-.04-.08. Not using it anymore....
thanks alot IC let me know if any more info or pics are needed.

 

[MynameStitch]

your prohblem is simple, your soil mixture..... cactus soil is acidic for cactus...... also by now they are hungry the pH spotting you see that is white is due to the pH not being in check..... you are also overwatering them badly...... You want to have no problems when growing seedlings, get miracle grow seed starter mixture, the best seed starter mixture you can by at a hardware store; all my grows are grown with it and I never NOT ONCE had a problem and I have grown out a lot of strains and all grew the same with no problems......

As for yours how do you check the pH when you do not collect the run off from the bottom of the cups?

There is holes in those cups right?

You need to do is stop watering so much, or so heavily.....

They need different soil; get a different brand of soil..... you can use mg organic mixture if you like just dilute it a bit with a different brand that has no nutes in it.
Or get a different brand than mg all together......

do not get any other brand of mg products or you will burn your plants......

Seems like cactus soil is weak in phosphorus, that spotting you see in between the veins is phosphorus, it is needed to help roots grow and other things.

Some people hate MG products, it is good if you know how to use them and use them CORRECTLY.

So you need to stop watering so much, correct the pH if you keep it in that soil and feed small dosage... fish emulsion is fine to use; but not in this instance...... you need a more balanced fert........

First check the run off to see what your pH is and then you can go from there about correcting it with dolomite lime.....

 

[Rob547]

Hey Stitch thanks for coming by!

Don't really know where to start but..
Soil....I know it sucks, the main reason I have been using it is because my normal soil has too much shit in it to start seedlings. Like I mentioned above I've ditched the MG. I've started putting them from germ to jiffy cubes to soil. Just got a new soil, seems to be pretty good, Fafard Seed Starter potting mix, the ones in it now seem healthy.
Ph...What I meant is that I've checked the water out of the tap for ph, haven't checked the runoff yet. Just too make sure it was ok.
Watering....I really didn't think I was overwatering. I usually wait till they get pretty droopy before I water. Maybe I just give them too much at a time? I'll work on it though. Oh and the cups do have 4 holes in the bottom for drainage.
I also use MG ferts, which is probably why I ended up with the soil. I've always had good luck in veg with it, the 24-8-16 and the 18-18-21. (not used with MG soil)

thanks again

 

[MynameStitch]

The tap water is not what you want to worry about, it's what is in the soil that changes the waters pH is what you want to worry about, after you water your plants you collect the run off from the bottom of the cups and then you test that pH.

I think it's more that you give them too muich at a time and watering too soon rather than too often.

When you use mg products you got to be careful, cause it's so strong it's not even funny... I would get a different brand if I were you, but if you don't got any money something is better than nothing...

do not listen to there directions..... for your size plants use 1/4 teaspoon per GALLON of water and when they get bigger 4 sets of leaves or more 1/2 teaspoon per gallon of water.

When you get a nutrinet that is strong like that and you have to cut the dosage your not giving your plants the % that is listed on the back, so even though you think you are giving them enough of something.... remember since you got to cut the dosage your cutting there % too, so when they start to show issues; you either have to slightly adjust it or get something different altogether.

 

[Rob547]

So I did test the run-off a few min ago....came out as 6.5 give or take a little, not the most accurate method but still should be good enough to not cause problems....idk
Yea, usually my first feeding or two are not even 1/4 tsp/gallon just to be safe. Directions say 1 TBS/gallon I don't think I've ever given them that much. Good point too, not only in the macro but the micro nutes, probably wouldn't have occurred to me that that alone could cause problems.

 

[mexilandrace]

that plant is way over watered right off the top

 

[MynameStitch]

cactus mixture is soiless mixture meaning the mixture pH is going to be needing to be a little more acidic....... yours is just .2 over which would cause issues not to mention it's in the higher range.......

5.5 to 6.3 is the range....
I would try to get a better pH tester too, do not get the soil probe ones, those don't work for crap.

ph test strips or a pH pen is the best to use.

 

[Rob547]

Ah, I see. I thought the range was ~6.3-6.8 regardless of what it is in. (excluding hydro)