300 watt mars hydro 4ft cabinet grow

theinhibitor said:

Looks fine but I hope you are not trying to veg in all of that purplish light. My veg LED is white light, like 80% white light. If you dont have a veg setting on this LED, buy some T5's and grow over them for 3-4 weeks, should only cost you ~$100 or add some 6500k CFLs, maybe 2 would do it.

Also, try to set your LED lower, like way lower. Should be around 18-24" from the tops of your plants. This looks like its 4ft away lol.

And if it is DWC, you might want to invest in a chiller, or probe chiller. You can easily, using a circle saw, cut the side of this tub and add a probe chiller for around $150, and then you wont have to worry about water temp which is a huge killer in 1st time DWC.

Eh, let me make a list with top priority being first:

1. Move light down to 18-24" from plant tops. Add some more white light if possible.
2. Cover up unused pots or any holes in top cover - any light that hits the reservoir water is light than will cause algae blooms
3. Make sure your water temp is around 65-75C, if higher add probe chiller (cheapest form, ~$150)
4. Air stones. Add as many as you can. I would suggest looking for ones with small pore sizes, like this one:
https://www.amazon.com/gp/product/B00SF17UPY/ref=oh_aui_search_detailpage?ie=UTF8&psc=1
5. Post more details: system, # of plants, strains, temperature at night, temp during day

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frizzayy said:

Ur the man I have 2 autos one dying as I'll show u temp at night I was doing 24/0 now 20:4 starting today was 68 daytime mid to low 80s and yea I deff need to move that light but honestly they haven't stretched at all there staying tiny for auto haze I thought maybe the light is fine but honestly I listen to ppl here over the recommended height

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frizzayy said:

And can I add like side lighting for the white light is there something that's cool to the touch or impossible ?!

Click to expand...

theinhibitor said:

Cool to touch? Probably only LEDs, CFLs can get pretty hot.

Do you have AC or central air? If not, you could go try to go 20/4, making the 4 hours off during the hottest part of the day so turn off at 10am and back on at 2pm.

Right now though, I can tell that actually the lighting is the least of your problems.

The big to do - I assume you are growing in coco in DWC. Ditch this immediately. Coco is hard to master, even more so in DWC, and I can tell your plants are not liking it. There are so many things that can go wrong with coco, any advice I give would have you running around buying and trying various things that probably wont work.

First thing to do immediately - let it dry completely, like dry to the touch. You could be flooding and drowning them. Once completely dry I would sit these plants in just water fortified with silica.

(1/2 tsp per gallon of Dyna Gro Pro Tekt or similiar: link)

and maybe even move them outside honestly (if temps are cooler outside). Dont worry, no one will know its MJ at this point lol.

Ditch your res for now. Clean it out and empty it. You will need to hand water these guys until they pickup and grow some major roots.

Ill make a list again:
1. Buy 3 gallons of steam distilled (look for it on the label) of water at your local store
2. Empty your res. Completely. Clean and dry.
3. Let your coco dry out until there isnt any wetness even if you dig your finger an inch into the coco
4. Put some silica (1/2 tsp) into the distilled gallon and soak the little ones in it for about 4 hours. If they start to wilt, take them out and let them dry out again. You should do all of this in the coolest place you can find, dont use the light.
5. Put them into the empty system and use the other 2 gallons you bought to make 2 gallons of whatever nutes your using. Do not spray them. Do not use any kind of foliar feeding (looks like one might have burn spots). Only add water when you cant feel wetness or when your plants start to wilt. You're going to have to baby them to save this one and it might take a while (3-4 days).
6. If your plants pick up but are still yellowing, I would replant in hydroton. It drains and is easier to maintain.

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frizzayy said:

This guy knows his shit ty man the only thing I'm worried when I take them out these roots will be hanging on this one plant as in they are 5-6 inches long floating in my resv u think it's ok just be careful ? I took the one who really looks like its dying out to dry her but what u said about burn spots i was just looking that up can that be it on the nice or nicer looking one ? I haven't misted in days tho maybe the water is shooting up from the resv?? Ty u weed growing god

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frizzayy said:

also I have a ac unit right behind the sucker it's just not directly blowing air on it fresh air in the cabinet I know I mastered it feels great in there I think I'm gonna listen to ur advice n try this chemical scientific shit ur saying man weed is harder then ppl say least hydro ....fun af tho

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theinhibitor said:

Cool to touch? Probably only LEDs, CFLs can get pretty hot.

Do you have AC or central air? If not, you could go try to go 20/4, making the 4 hours off during the hottest part of the day so turn off at 10am and back on at 2pm.

Right now though, I can tell that actually the lighting is the least of your problems.

The big to do - I assume you are growing in coco in DWC. Ditch this immediately. Coco is hard to master, even more so in DWC, and I can tell your plants are not liking it. There are so many things that can go wrong with coco, any advice I give would have you running around buying and trying various things that probably wont work.

First thing to do immediately - let it dry completely, like dry to the touch. You could be flooding and drowning them. Once completely dry I would sit these plants in just water fortified with silica.

(1/2 tsp per gallon of Dyna Gro Pro Tekt or similiar: link)

and maybe even move them outside honestly (if temps are cooler outside). Dont worry, no one will know its MJ at this point lol.

Ditch your res for now. Clean it out and empty it. You will need to hand water these guys until they pickup and grow some major roots.

Ill make a list again:
1. Buy 3 gallons of steam distilled (look for it on the label) of water at your local store
2. Empty your res. Completely. Clean and dry.
3. Let your coco dry out until there isnt any wetness even if you dig your finger an inch into the coco
4. Put some silica (1/2 tsp) into the distilled gallon and soak the little ones in it for about 4 hours. If they start to wilt, take them out and let them dry out again. You should do all of this in the coolest place you can find, dont use the light.
5. Put them into the empty system and use the other 2 gallons you bought to make 2 gallons of whatever nutes your using. Do not spray them. Do not use any kind of foliar feeding (looks like one might have burn spots). Only add water when you cant feel wetness or when your plants start to wilt. You're going to have to baby them to save this one and it might take a while (3-4 days).
6. If your plants pick up but are still yellowing, I would replant in hydroton. It drains and is easier to maintain.

I just built this DWC system for a friend using hydroton and rooter cubes, since its the easiest to maintain. Even he had problems starting, but I came over and helped them out by flushing with distilled water. They are doing great now:
View attachment 4027800

If this grow doesnt work out use starter cubes: link. and plant in hydroton after a few days when they sprout:

If you have heat issues, every gallon will need to be fortified with silica. Silica will help the plants produce hardier skin and make them more heat resistant.

Click to expand...

frizzayy said:

Also I am not using nutrients yet straight 6.0. Ish water

Click to expand...

theinhibitor said:

Cool to touch? Probably only LEDs, CFLs can get pretty hot.

Do you have AC or central air? If not, you could go try to go 20/4, making the 4 hours off during the hottest part of the day so turn off at 10am and back on at 2pm.

Right now though, I can tell that actually the lighting is the least of your problems.

The big to do - I assume you are growing in coco in DWC. Ditch this immediately. Coco is hard to master, even more so in DWC, and I can tell your plants are not liking it. There are so many things that can go wrong with coco, any advice I give would have you running around buying and trying various things that probably wont work.


First thing to do immediately - let it dry completely, like dry to the touch. You could be flooding and drowning them. Once completely dry I would sit these plants in just water fortified with silica.

(1/2 tsp per gallon of Dyna Gro Pro Tekt or similiar: link)

and maybe even move them outside honestly (if temps are cooler outside). Dont worry, no one will know its MJ at this point lol.

Ditch your res for now. Clean it out and empty it. You will need to hand water these guys until they pickup and grow some major roots.

Ill make a list again:
1. Buy 3 gallons of steam distilled (look for it on the label) of water at your local store
2. Empty your res. Completely. Clean and dry.
3. Let your coco dry out until there isnt any wetness even if you dig your finger an inch into the coco
4. Put some silica (1/2 tsp) into the distilled gallon and soak the little ones in it for about 4 hours. If they start to wilt, take them out and let them dry out again. You should do all of this in the coolest place you can find, dont use the light.
5. Put them into the empty system and use the other 2 gallons you bought to make 2 gallons of whatever nutes your using. Do not spray them. Do not use any kind of foliar feeding (looks like one might have burn spots). Only add water when you cant feel wetness or when your plants start to wilt. You're going to have to baby them to save this one and it might take a while (3-4 days).
6. If your plants pick up but are still yellowing, I would replant in hydroton. It drains and is easier to maintain.

I just built this DWC system for a friend using hydroton and rooter cubes, since its the easiest to maintain. Even he had problems starting, but I came over and helped them out by flushing with distilled water. They are doing great now:
View attachment 4027800

If this grow doesnt work out use starter cubes: link. and plant in hydroton after a few days when they sprout:

If you have heat issues, every gallon will need to be fortified with silica. Silica will help the plants produce hardier skin and make them more heat resistant.

Click to expand...

theinhibitor said:

Hmm that may also be a problem...buy the silica supplement I linked. If anything, add that to the water. Make sure to adjust PH after.

You should be using a bit of grow, like 1/8tsp per gallon at least. I use Dyna Gro, they have Pro-Tekt (silica), Mag-Cal (magnesium-calcium), Gro and Bloom formulas. Just these 4 will be enough to get this:

View attachment 4027820

I think maybe over watering is the problem here. Definitely let it dry completely. If you've been using water, add a small bit of gro (1/8 to 1/4 tsp per gallon) and hand water them once dry. See if they pick up.

Click to expand...

frizzayy said:

And can I add like side lighting for the white light is there something that's cool to the touch or impossible ?!

Click to expand...

frizzayy said:

And can I add like side lighting for the white light is there something that's cool to the touch or impossible ?!

Click to expand...

theinhibitor said:

Hey np, praying for your little ones, hoping they will pull through.

Click to expand...

theinhibitor said:

Cool to touch? Probably only LEDs, CFLs can get pretty hot.

Do you have AC or central air? If not, you could go try to go 20/4, making the 4 hours off during the hottest part of the day so turn off at 10am and back on at 2pm.

Right now though, I can tell that actually the lighting is the least of your problems.

The big to do - I assume you are growing in coco in DWC. Ditch this immediately. Coco is hard to master, even more so in DWC, and I can tell your plants are not liking it. There are so many things that can go wrong with coco, any advice I give would have you running around buying and trying various things that probably wont work.

First thing to do immediately - let it dry completely, like dry to the touch. You could be flooding and drowning them. Once completely dry I would sit these plants in just water fortified with silica.

(1/2 tsp per gallon of Dyna Gro Pro Tekt or similiar: link)

and maybe even move them outside honestly (if temps are cooler outside). Dont worry, no one will know its MJ at this point lol.

Ditch your res for now. Clean it out and empty it. You will need to hand water these guys until they pickup and grow some major roots.

Ill make a list again:
1. Buy 3 gallons of steam distilled (look for it on the label) of water at your local store
2. Empty your res. Completely. Clean and dry.
3. Let your coco dry out until there isnt any wetness even if you dig your finger an inch into the coco
4. Put some silica (1/2 tsp) into the distilled gallon and soak the little ones in it for about 4 hours. If they start to wilt, take them out and let them dry out again. You should do all of this in the coolest place you can find, dont use the light.
5. Put them into the empty system and use the other 2 gallons you bought to make 2 gallons of whatever nutes your using. Do not spray them. Do not use any kind of foliar feeding (looks like one might have burn spots). Only add water when you cant feel wetness or when your plants start to wilt. You're going to have to baby them to save this one and it might take a while (3-4 days).
6. If your plants pick up but are still yellowing, I would replant in hydroton. It drains and is easier to maintain.

I just built this DWC system for a friend using hydroton and rooter cubes, since its the easiest to maintain. Even he had problems starting, but I came over and helped them out by flushing with distilled water. They are doing great now:
View attachment 4027800

If this grow doesnt work out use starter cubes: link. and plant in hydroton after a few days when they sprout:

If you have heat issues, every gallon will need to be fortified with silica. Silica will help the plants produce hardier skin and make them more heat resistant.

Click to expand...