Aeroponics question

[RonT]

Anyone using Aeroponics, Mega Crop and tracking PPMs?

My PPMs keeping going up over night without me giving nutrients.
its almost like my water and chemicals are brewing and getting stronger as a go.

are you experiencing anything like this? Is this normal?

my PG has been averaging between 5.8 and 6.1

I using about 1.5 gallons of water a day

 

[TorturedSoul]

Or the grit didnt complete disolve and wont go through your shit cause small holes IdK

 

[RonT]

Thanks TS, one thing I forgot to mention is my plants look absolutely beautiful. What ever is going on there is zero change in leaf color and it seems to be growing real fast

 

[RonT]

Here is a chart of my chemicals.
I use 1 tsp of mega crop, 1 tsp calmag, 2 ml hydrogaurd and 2 ml PH Down per gallon when I refill. When I top off daily i use 1 tsp calmag, 2 ml hydrogaurd and 2 ml PH Down.

I change the water every two weeks the PPMS just keeps rising.

	Water usage 24 hours	PH	PPM	Temp
1-Oct	0	6	6.95	7.7
2-Oct	1	6.1	7.59	7.6
3-Oct	0.25	6.6	7.39	7.8
4-Oct	1	6.2	8.12	7.8
5-Oct	1	6.3	7.62	7.7
6-Oct	1	6.3	7.75	7.7
7-Oct	1	6.2	7.95	7.8
8-Oct	1	6.2	7.33	7.9
9-Oct	1	6.1	7.25	7.8
10-Oct	1.25	6.3	7.18	7.7
11-Oct	2	6.2	7.38	7.7
12-Oct	1.5	5.8	7.38	7.7
13-Oct	1	5.9	7.47	7.7
14-Oct	2	6	7.92	7.6
15-Oct	1.5	6	8.18	7.6
16-Oct	1	6.1	8.58	7.4
17-Oct	1	5.6	8.77	7.4
18-Oct	2	5.6	8.55	7.6
19-Oct	1	6	9.22	7.4
20-Oct	2	6	9.5	7.5
21-Oct	2	6.1	9.96	7.5
22-Oct	2	5.5	9.81	7.7
23-Oct	2	5.7	9.83	7.8
24-Oct	2	6	14.6	7.4
25-Oct	2.25	5.8	10.7	7.4
26-Oct	2.5	5.8	10.6	7.4
27-Oct	2	6.1	10.4	7.5
28-Oct	2	5.9	10.9	7.4
29-Oct	2	5.9	11.1	7.5

 

[lvumlow]

I may be wrong since I am new to this but mine does the same thing every once in awhile. I found this forum in search of optimizing nutrient uptake and hope we get more feedback from others.

In my case, when my nutrients levels increase I correct the resovoir and flush the root chamber long enough for everything to cycle a few times with the corrected levels. I will usually see the levels rise again but keep correcting until it stabilizes then it stays stable for a good period of time which leads me to consider it to be build up. Your plants can both uptake and release nutrients when levels are too high so try backing your levels down gradually until it stabilizes.

I had a pretty large spike today right after I elevated the root chamber on one side to help drain it. Mine is in mid flower and consumes over a gallon a day (one small plant) so your consumption doesn't sound bad.

Stupid question, but have you confirmed your numbers with another instrument and/or calibrated? I always double check with another device; especially if you have any auto dosers (pH or EC) running.

Interested to hear what you find...

 

[lvumlow]

Please forgive the hijack but I am new and would love to understand what TDS scale people are assuming when referencing ppms (Hanna, Eutech or Truncheon)? This is my first grow and without any guidance I have only been referencing EC to avoid that confusion.

Is there a standard that everyone assumes by default because there is a 200ppm range between the three.

I can see from my own experience that flushing or cycling with corrected levels seems to stabilize for awhile. If I didn't know better, I would reduce the nuts until the levels stabilize or drop.

 

[TorturedSoul]

We really should all be using EC. That's the only thing that a "TDS" meter actually measures anyway. They then multiply it by a "conversion factor" to display a parts per million number - which is almost never accurate, because the solution being measured does not have the correct makeup (such as water that contains only sodium chloride, which is the one solution that the meters that use 500 x EC in millisiemens (mS). Then there's the one referred to as the 442 conversion because it assumes the solution being measured consists of 40% sodium sulfate, 40% sodium bicarbonate, and 20% sodium chloride. That one uses approximately 700 x EC in millisiemens. Do either of these things match anyone's nutrient solution recipes? NO! There is a third one, but it's not any better (and is rarely used for this purpose).

"TDS" meters used to be uniquely an affliction(?) of people living in the USA. Apparently, the various manufacturers assumed we were too stupid to understand electrical conductivity (EC). Maybe because so many of us still appear to have difficulty understanding the metric system - which is one of the simplest things we've yet come up with as a species , to convert from one metric measurement to another, just move the decimal point. The usage may have spread to other parts of the world now due to all the USA-based cannabis forums on the Internet, IDK.

Again, these things are only accurate if the solution being measured exactly matches what the manufacturer based its conversion factor of. EC, while not exactly being drastically better at telling someone what - and how much - is in their nutrient solution, is at least a real, measured thing.

I've known people employed in the municipal water- and wastewater-treatment industry, and have (upon occasion) been screwing around in their labs when they needed to accurately measure total dissolved solids. How do they do this? They take a sample of a certain amount of liquid, walk into the lab... and flash boil it. Then they weigh the residue on a scale that is so accurate and has such high resolution that is located in a glass box, on a granite (marble? I don't remember, but it's some kind of stone) table that is sitting on a very solid floor - this is to prevent anyone walking around in the room, or even random air currents produced by a person passing by, from affecting the reading. If you're not going to do that, lol... use an EC meter that actually displays the result as EC (generally in millisiemens (μS/cm)). Or at least find out what conversion factor your "TDS" meter uses to mangle its EC measurements, and convert them back before posting, so that everyone who reads it will understand exactly what you mean. And feel free to post my... er... rant whenever and whenever the question comes up; education is a wonderful thing, when we can get it.

 

[lvumlow]

Thanks for the additional information. This is my first attempt at growing indoors let alone trying to build a complete DIY Aero configuration so I guess I got lucky by using EC from the start.

Always appreciate someone taking the time to help others with this kind of detailed information...

 

[lvumlow]

I always seem to miss the dates on these posts so sorry to revive such an old thread but I guess newbies like me are new to this site all the time so hopefully it will be helpful information to someone...

There doesn't seem to be much going on with respect to aero on the site these days...

 

[RonT]

Or the grit didnt complete disolve and wont go through your shit cause small holes IdK

I have a question about this chart. How long of a time period do you use to determine rising falling or static. Average over 3 days fours days?

 

[lvumlow]

In aeroponics, everything is accelerated in terms of time. With that being said, changes generally don't occur immediately so you always have time; just not the same time when growing in soil which serves as a buffer.

For me, I keep a rolling log throughout the day (maybe 4 or 5 readings) on a dry erase board and watch for trends. Usually if something is drifting, it will be consistent or even accelerating so I make corrections as soon as I feel something is changing consistently. If I feel like I got to the problem late, I will flush everything to ensure the whole system is corrected.

I believe the reaction time in aeroponics is usually a couple of days whereas soil can be a week before the plant with show signs of the environment. I try to correct any problem immediately just to keep my guard up. Problems usually show up when you least expect it, so you want to pay attention to all parameters in real time.

 

[RonT]

Ok thanks for the information, sorry about the chiefs

 

[lvumlow]

Lol, Damn Brady!

 

[Jeremy6232]

As the plants use water they may not be using the nutes that are in the water increasing your EC seems like an addition of RO/DI water a top off in the morning may be needed to keep your EC consistent.

 

[lvumlow]

As the plants use water they may not be using the nutes that are in the water increasing your EC seems like an addition of RO/DI water a top off in the morning may be needed to keep your EC consistent.

My EC is very stabile ... for 4/5 days, then starts to climb slowly. If I flush, I will see EC levels as high as 5.0 on the first run so the question is what is leading to the build up? My current theory is sedimentary accumulation (the plant shows no sign of nute burn). My next chamber will not have a flat bottom to test that theory...

This situation has occurred like clock work over the last 2 months... every 4/5 days...

Also considering using a 2 stage resovior next run to correct more data.

 

[leblanca]

My EC is very stabile ... for 4/5 days, then starts to climb slowly. If I flush, I will see EC levels as high as 5.0 on the first run so the question is what is leading to the build up? My current theory is sedimentary accumulation (the plant shows no sign of nute burn). My next chamber will not have a flat bottom to test that theory...

This situation has occurred like clock work over the last 2 months... every 4/5 days...

Also considering using a 2 stage resovior next run to correct more data.

Could be a build up of salt on the roots?

 

[lvumlow]

Could be a build up of salt on the roots?

Funny, I was just posting up some observations in another thread about ways to explain it...

timings-for-nutrients-with-aeroponic-set-up

Will be interested to hear your thoughts...

 

[leblanca]

Funny, I was just posting up some observations in another thread about ways to explain it...

timings-for-nutrients-with-aeroponic-set-up

Will be interested to hear your thoughts...

Hmm link doesnt work for me.

 

[lvumlow]

Yes, not sure why It is not working. It is in the same group of posts...

 

[Gforce3]

With aeroponic growing your ppm should drop some every day. If your ppm is rising you either have too many nutrients or some type of salt build up or lock out. A perfect aeroponic reservoir drops daily. If it stays the same you are boarder line, if it raises something isn’t right. Flush roots for a couple hours and start at a lower ppm/EC. If it drops more than 20-40ppm add nutrients. If it raises lower nutrients. I keep mine at a level that’s drops 20ppm a day and my plants stay healthy the entire grow. Once I allow my res to raise I experience nutrient burn