Three types of hydro in a small tent on one airpump?

Indoor Growing Hydroponics
#125

Some slightly encouraging news. This morning the PH had risen from 5.69 last night to 5.94 after 10 hours. Thats a big improvement from what it was doing. I can only assume that lowering the PH in the rez way down and/or flushing the system has helped in some way. I hope it used up or neutralized some of what ever is buffering the PH up so much.

I picked the best three clones and put them in to the totes. The one with the most/longest roots went into the NFT tote. The roots have the furthest to go to reach the water level in that tote. I put the one with the shortest roots into the E/F tote and the last one into the Membrane tote.

The new growth on all three is looking pretty good.

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Im going to monitor the PH change closely for the next several days and if it doesnt settle down enough, I will start playing with my idea for a slow acid delivery system.

On another note, Ive decided to keep the rez temp around 66 deg F for now. The hope being to reduce risk of root issues with the lower temp.

I had been planning to run a sterile rez using pool shock - mainly for cost reasons and its simplicity.

BUT - then I read a scientific study on the use of chlorine, chloramine, H2O2, etc to treat and prevent root pathogens. According to that study, if you run high enough levels of chlorine, etc to actually kill the pathogens, it damages the roots and reduces growth. Running at levels that dont hurt the roots doesnt kill the bad stuff. Plus, active chlorine combines almost instantly with nitrogen in the nutes which reduces the availability of both in the system. Over all, that made it sound like a bad idea to go sterile with no up-side at all. Well, the one up-side would be if you went sterile from the beginning at moderate doses of chlorine, you might be able to prevent root pathogen growth from getting started - maybe - but at the cost of some damage to the roots.

Anyway, I decided to skip the chlorine and just keep temps down as long as possible. I will have some extra funds in a couple of weeks and will order some Hydroguard to use instead.

#126

I would not worry too much about pathogens, especially in a system you are using for the first time. Normally, you notice by crop three or four whether you are going to get any. Best way to stop pathogens is sweep up dead leaves, keep humidity down outside your tent, and keep your nute solution around 21-22c.

You look as though you are keeping things tidy enough, I would not worry too much about things until you notice an issue. Main worry is Spider Mites. Learn to recognise and deal with those and you will mitigate the major headache with growing.

From the look of them, they need the PH adjusted and a huge dose of LITFA. Food in the water, water at 21-22c, PH adjusted. Nothing else…

Pathogens are restricted greatly at 21c, ideal temps for roots are between 22-24. Much colder than 21 and you will stunt growth from the nute solution being too cold.

Try staying closer to 70f than 69 (or 66!) and you will still be fine for pathogens, but you will not be stunting your plants. 71.5 is still fine, 75 is the top limit for vigorous growth and where you are just starting to have a greater risk of root rot etc.

so, 68 or less =ouch 69-70=low end 71-73 optimal 74-75 still fine but at the warm end 75 or more=ouch

If root rot concerns you, that is if you know you have had it in that system before, stay to the low end.

If you have not had root rot in that system before, either it is new or you have bleached+scrubbed it or similar, you could go as high as 73 regularly and have no concerns. You would pretty much have to manually introduce root rot to suffer from it the first time you use a system.

You are currently at ‘ouch’, which will limit nutrient uptake and if you go just a few degrees lower (more like 59 degrees) will stop the plants growing altogether.

Remember, half measures with tiny babies. Not full measures, or double measures.

90% measure=90% yield
100% measure=100% yield
105% measure=50% yield…

EDIT :
From the sounds of it, that pool shock stuff would be good for cleaning your system in-between crops.

That is the time for double measures, when there are no plants in it.

if you can reduce your pathogens to zero between crops, it is very unlikely that any pathogen will spread enough in a single cycle to become an issue.

Then you can relax and watch the flowers grow :wink:

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#127

Thats an excellent explanation and very good news. Ok, I dialed up the temp on the controller to 72. The way mine works, that will keep the temps between 71-72 F in the rez. At least until my room temp gets too hi.

Thanks again for the help!!!

#128

Ok, its been almost 24 hours and the rez has gone from a PH of 5.69 up to 6.34. Thats a big improvement from before, so I have hope it will get even better over time.

Oh - and the clones have been in the system for over 12 hours and they are not dead yet, so Im not screwing it up toooo badly - so far :wink:

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#129

Its been another 18 hours and the PH has only risen to 6.49, so there seems to be an upper limit to the buffering - which is very very good news. Its been going up slower and slower as time went on and it slows down a lot as it gets above 6.3.

The question now is, how soon should I ph back down to 5.5 or 5.8?

The roots are not in any direct contact with the water yet - they are still getting top fed by me once a day plus what ever wicking is going on.

I think I will go ahead and try some of the battery acid mix I made to see how much it takes to drop the PH back down so I know that for future reference. It will be safer to do that now before the roots get into the water directly.

#130

I decided to drop the PH back down to 5.5 last night using the sulfuric acid mix I made up. I dont know if its the sulfuric acid or if Im finally neutralizing what ever is buffering the PH up, or more likely some of both, but the PH is going up a lot slower now.

In the last 24 hours, its only gone up from 5.51 to 5.92.

Im liking this trend and hope it continues…

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#131

Looks like you cracked it. It can take a few days or so for a medium to settle down. Lots say that about coco too bro.

#132

Thanks. This is taking more like a few weeks, bit it seems to be getting there.

#133

wow sulfuric acid isn’t that stuff super corrosive?

if your water has co2 in it the PH will rise as the co2 gets off gassed. maybe things other than co2 affect the PH also, like chlorine etc. not sure

#134

I was like you and very leery of sulfuric acid - until I read up on it some more while looking for alternatives to PH Down.

PH Down is phosphoric acid - very nearly as corrosive as sulfuric acid. Also, nitric acid is often used which isnt much safer.

All of them are highly corrosive and dangerous to use, but the sulfuric isnt really any worse than the others as long as your careful with the ratios. All require exactly the same safety precautions.

Sulfuric acid is also the most used PH down product in general agricultural applications and commercial hydroponics applications. Thats probably mainly due to the lower cost. Its way cheaper than any other option and no worse health wise or risk wise.

I bought 1 qt of battery acid for $7 at the auto parts store. Im diluting it at a rate of 1 cup in 1 gal of tap water. That means I can make 4 gallons of PH down for $7. Four gallons of PH Down would cost me around $100.

The sulfuric acid is also supposed to last longer than the other options, as far as keeping the PH down, so you dont need to adjust as often.

My water has no chlorine/chloramine as far as I know - Im on a shared, community well and I ‘think’ its untreated in way way. I keep meaning to call the county water people to check on that, but havent done so yet.

The water does vary a good bit from day to day - I think depending on how much it has rained. Today its at a PH of 6.90, EC is 186uS, TDS is 89ppm. Last week it was at 6.84PH. Usually its between 7.1 and 7.5 PH and 120-200PPM, but its been raining a LOT lately. I live in Wa state and we got about 48" last year.

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#135

hey @Swayze apparently sulfiric acid lasts the longest for PH down, probably not organic though :smiley:

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#136

I know nothing about “organic”, but how can it not be organic? Its a naturally occurring substance - its a part of acid rain :slight_smile:

Or does it have to grow on a plant to be organic? Dont some bug eating flowers make it or is that hydrochloric acid? Obviously Im not big on botany or organic anything :slight_smile:

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#137

i have no idea what qualifies or doesn’t. i think the definition is naturally occuring. he was looking for it, organic isn’t a big deal to me :smiley:

#138

Ironically organic has no written standards. There are some items certified for organic farming through state agencies, but they consider environmental impacts as well as sustainability and the source.

In chemistry, organic means it contains a carbon atom.

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#139

Interesting and surprising lack of definition.

I always had the vague notion that “organic” growing mainly meant you didnt use pesticides and as a secondary plus, only compost for nutes. I never got the impression organic chemistry had anything to do with it.

#140

Thanks @legalcanada!

I’m mainly looking to have a long term water reservoir. And a long lasting PH down product so I won’t have to adjust constantly.

But I’m also looking to maintain the microbial life / benificial bacteria in my soil.

from what I’ve read there is a lot of opinions on both sides… I’m still pretty new so I figured I’d keep it as organic as possible to keep my soil life good and healthy .

  • SWAYZE
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#141

I am certainly no expert, but based on my reading, if sulfuric acid is used in commercial hydro and general agricultural applications, it cant be hurting the soil bacteria. As long as you keep the PH in range, you should be fine on that level. Its letting the PH swing too far that can hurt.

One down side to the ‘organic’ acids like vinegar, citric acid, lemon juice, etc is the other, non-acid organic parts of those products. They contain sugars and other organic (as in organic chemistry) compounds. Things that can feed bad bacteria. One of the reasons I skipped over those options - other than that they dont last very long - is several reports I read saying that people has scum/slime issues in the rez and water lines when using them.

Of course, as is almost always the case in growing - there are a ton of people who swear by using them and have zero issues :slight_smile:

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#142

Its been 12 days since I put the clones in the system, so time for an up-date and some observations.

  1. The PH issue is now a non-issue. Still dont know if its because I switched to using sulfuric acid instead of GH PH Down, or if I just finally neutralized what ever was in the lava rock and perlite. I suspect some of both, but Im happy now. PH is very stable over several days with just a very slow rise.

  2. The clones are growing and looking pretty good - but - it is going much slooooower than I had hoped or anticipated. Im sure its due to me nuking them almost to death with the Neam oil treatment. The new growth looks good but the older leaves that got the neam treatment still have signs of the trauma.

  3. I am finally starting to see some roots growing down towards the water in each tote. The EF tote has the shortest distance to go and one root is almost touching the hi water level. The other two still have 4" or 5" to go.

I think thats a screw up on my part. I should have changed things around so that the rockwool cubes were much closer to the water level in all the totes - so the roots had less distance to go, or at least it was more equal. In other words, the Membrane and NFT totes should have been shorter. Too late to change now though.

  1. The water level in the rez drops about 1 gallon every three days. That seems manageable to me. At this point, I think thats mostly due to evaporation. I doubt these small clones are using that much water.

  2. I just realized another screw up I made - I have no way to tie anything down to do LST. Im a big fan of bending stems sideways while the plants are young, but I have no way to tie them down. The entire top of the grow area is removable foam pieces, so I can get into the root zone if I need to clean out drains etc. Im going to have to get creative somehow. This strain is mostly sativa and grows to over 6 ft tall and my tent is only 4ft tall! I was planning to do a scrog. I may have to do some more stressful topping or super cropping.

Here is what the clones looked like when I put them in the system and how they look now.

E&F (left tote)

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NFT (middle tote)

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Membrane (right tote)

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The two “extra” clones are dong just as well in their small dixie cups, but they are going to be getting root bound in another week or so at the rate they are going.

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#143

I typed this up this last Tuesday but never got around to posting it, so here it is.

Im on day 20 since putting the clones in the system so time for an up-date.

The short version of the report is that I cant tell any significant difference - so far - between the three types of hydro. All three clones are growing at pretty much exactly the same (sloooooow) rate. Even the two “extra” clones that I stuck in crappy “hempy buckets”, and mostly ignore, are doing just fine and growing at exactly the same rates.

Ive been worried about being able to control temps in the tent from the beginning. Thats why I was wanting to get started before it got too warm, but things didnt go as planned. I waited for seeds that were slow to arrive, then tried to kill my clones with Neem oil. Those two things put me at least a month behind schedule. The clones have recovered fairly well, but are growing sloooooooowly.

Last week the outside temps jumped 10 degs to the low 80’s and it was bad. I dont have house AC or even a window AC in the grow room, and room temps went up into the upper 70’s and temps in the tent went up to the upper 80’s. I had to remove the door to the tent and put some extra fans in the room just to keep temps in the tent in the low 80’s. Surprisingly, the rez temps stayed just fine at no more than 72.

All five plants are getting very bushy, but are not growing taller to any real degree. The fan leaves are getting huge, but almost no stretch or vertical growth. I can only assume the Neem torture I did early on is the reason. This strain - Blue Dream - is supposed to grow to over 6ft in height, but it sure doesnt look like these babies will do that unless maybe I veg them for another 6 months - which is not going to work.

The weather is going to be getting hotter, so I have decided to go ahead and change to 12/12 and hope they finish before it gets too hot. Im afraid if I try to wait for them to start growing more, I will loose them all to heat stress before they mature. I wanted to do some LST, SCROG, etc, but it doesnt look like thats going to happen. At this point, I will be happy to get them to any kind of harvest.

The root growth has also been slow. At least I was expecting it to be much faster than it has been. Again, I assume its the Neem Death curse. It has been interesting watching the roots make there way out of the perlite they are growing in and working their way into the hydro systems.

So far, the Ebb/Flood tote was the fastest for showing root growth, but I think thats just because the roots had the shortest distance to travel.

One surprising thing to me is in the NFT and Membrane totes, one single root made it out of the perlite - through a hole in the side of the tower - and down to the batting/fabric. Why that one root chose to grow like crazy while a dozen others stayed short and continue to grow slooooowly I have no clue.

In both cases though, that one long root hit the batting/fabric on the bottom of the tote and just stopped dead! They did not and have not grown down into the fabric. Instead, they keep getting longer, but the root just loops around in the air - above the fabric - while the end that hit the fabric stays exactly where it hit without growing into the fabric or moving at all. They both then started to send out dozens of side roots which are doing the same thing. They grow down to the fabric and stop. As they get longer, they just lift the main root higher above the fabric.

I even moved the root ends around and finally covered the roots with another piece of fabric to see what would happen, but so far, they dont seem to want to grow IN to the fabric.

This is not how it went in those videos.

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#144

Ok, two days later and time for another up-date. Short version:

#1) is the E/F clone. Its growing the bushiest and tied for tallest.
#2) is the Membrane clone. Its almost as tall as the E/F clone but not quite as bushy. It does seem to be growing slightly faster though.
#3) is the NFT clone. Its not far behind the other two, but is definitely in 3rd place. It had been in 1st place as the fastest and tallest just a few days ago, but is now falling behind.

Wow! What a difference two days makes! My last report from last Tuesday was all gloom and doom, but the very next day, they all suddenly started to grow and bush out much faster! They still are not very tall, and they seem to be getting bushier faster than taller, but its a big improvement. More importantly, they have started to drink a lot more water every day. So far they have gone from about 5.5" tall to 8.5" at the tallest.

I have been top feeding them by hand until the roots get established at the water level. The E/F tote got there first and it is growing the bushiest by a significant margin. The NFT is lagging behind the other two a bit. Interestingly, the Membrane tote is growing vertically just as fast as the E/F tote, but is not quite as bushy or big around. It also finally started to drink all the excess water that is left in the bottom of the tote on top of the membrane after I top feed. I make a point ot scoop out as much as possible, but that always leaves maybe a 1/4 cup sitting on top of the membrane. The last two days, all that water has been sucked up in roughly 3 hours. Just a few days ago I could not tell if any had been used at all.

All three must be drinking now because the rez level has been dropping much faster the last two days - its up to maybe 1 gal a day from maybe a couple of cups per day last week.

The roots are still growing noticeably every time I check them, which is every 3 or 4 hours lately. However, it still feels like the root growth is pretty slow and anemic compared to pics Ive seen of other grows. They also still dont seem to want to grow into the fabric matting.

I see I forgot to post pics above. I will try to do that tomorrow.

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