Adventures in Hydro #2 - LP Aero/NFT mash-up - or - switching to HPA?

Im going to have to look that strain up. Sounds awesome!

I think these C99 plants would do much better if I cut the veg time way down too. These roots are still growing, and Im within a week or two of harvest. At a best guess, Im somewhere over of 30-35 gallons of roots in my 48 gallon chamber.

1 Like

Looking forward to your analysis of the overall results!

1 Like

Me too! Im almost more excited about pulling the root ball out of the chamber for a good close look than I am about the harvest :slight_smile:

Unfortunately, Ive been loosing fuzzies for the last two weeks or so, and especially over the last few days with the system being turned off twice for hours at a time. Im sure the short heavy chlorine blast and now the steady chlorine at 2-4 PPM didnt help either.

Today, I am seeing possible signs that the algae is coming back in the system. Its been 4 days sinse I did the super heavy chlorine treatment. The rez PH has risen 0.1 in PH over the last 4 hours or so, and the tank and nozzles are staying 0.1 to 0.2 points higher than the rez. I just increased the chlorine to 6 PPM, but I doubt that will stop it. We will see.

This really is zombie algae crap. It just wont stay dead!

I hope I can get the roots out in one big chunk. They are tight against the chamber walls over probably 70-75% of the chamber. Im worried they have attached themselves tot he fabric. I might be fine though. I see no signs of roots on the outside of the chamber. If they dont pull out easily, I may have to cut around the perimeter with a long knife. Not sure how I will loosten the ones on the floor if they are stuck down.

One surprising thing to me is I also see no sign of mineral build up on the fabric anywhere. I was expecting to see a lot of mineral build up. The fabric certainly gets wet, and there is significant evaporative cooling going on, so I dont know where all those minerals in the nutes are going?

The heater I have in the space outside the root chamber comes on quite often and keeps the top of the chamber between 68F to 70F. The space between the chamber, and the insulated box I have around it, stays in the 70-74F deg range every time I check, yet the walls of the chamber feel cool and read 5 to 8 deg cooler. The only place the fabric walls feel wet on the outside is near and on the very bottom. Not what I was expecting.

Today is day 50 of 12/12 - the earliest the plant might have been ready. Its getting close, but not there yet. I see mostly milky trics, but very few amber ones yet and the pistils are still mostly white, but they are turning.

3 Likes

Looks a little overfed and undernourished. From the symptoms it looks like either zinc, manganese, iron, or copper. There is a slight chance it may be sulphur but I doubt that and I reckon the other elements are a better route of investigation.

All of those occur if your PH is too high, which can neatly be explained by the zombie crap.

For next time, I would try a little less food and a little more of a swing in the lower ranges.

I am interested to note that your plants are still putting out roots late into flower, I assumed my cutting was special in some way to do so. It may be that all plants continue to put out roots late into flower instead of the common ‘knowledge’ that they do not.

I often find myself looking at what is actually going on and then from an examination of facts, finding myself in conflict with ‘accepted knowledge’…

3 Likes

Good analysis. I over fed them badly when I switched to the AN nutes, and yeah, I figure I was often up in the 6.5 PH range or maybe higher, by the time the nutes got to the misters. I doubt they have seen a PH below 6 since somewhere back in veg - thank you zombie algae crap!

hehehehe stoner science, but you gotta love the enthusiasm! :smiley:

1 Like

The zombie algae is definately back in the tank and the rest of the system. The rez seems to be ok still.

The rez had risen to 5.7 so last night I drained the tank back into the rez and then dropped it back to 5.5 and re-filled the tank. The rez is still at 5.5 today - after two pump cycles.

However, the tank has gone from 5.5 to 6.0 and the nozzles are at 6.1, so somewhere in the system that crap is going strong again.

I dont think I want to repeat the harsh chlorine treatment, but Im not sure what other choices I have other than just let it go. Even if I set the PH in the rez to 5.0, the PH in the tank quickly goes to the 6 range.

Oh wait - I have MES now! I might try some of that later tonight. Too many errands to run today.

I seem to be living in ‘interesting times’ recently. Ive been so busy Ive barely looked at the plants themselves the last several days. This morning early, I realized they look significantly worse. I just had time to check PH and the nozzles were running at 6.5!!

All I had time for was to speed up the feed back drip back into the rez and then I had to run off again. This evening the plants look worse and the nozzles are still at 6.4-6.5, the tank is running 6.3 and the rez is at 5.6.

So, the rez is climbing slightly, but not bad. I think that may be because I added the second UV light to the rez. I was expecting the feed back drip to re-contaminate the rez, but it seems to be under control there.

The accumulator tank and the rest is obviously badly re-infected again.

I was really wanting to try the MES to see how well or if it worked to hold the PH under these conditions, but Im worried about how fast the leaves are burning up. Im going to be way busy tomorrow too, so I wont have time to re-check anything until late tomorrow at the earliest.

These leaves look a LOT worse than they did even two days ago.

On the other hand - which is worse - continuing at too hi a PH with obvious and serious nute lockout issues, or shock the roots and plant with no water for an extended time - for a third time in just a few days - and yet another heavy chlorine shot?

I am really getting to hate this algae crap. I may never watch The Walking Dead again…

Screw it. Im going to try the MES at 0.005M strength and see what happens. That should be on the safe side as far as concentration without causing other nute issues. My curiosity is stronger than my worry about the plant.

I just did the math and to treat the 8 gallons I currently have in the system at 0.005M or 5mM is going to take aprox 29 gms of MES. This bottle is 100 gms for $20, so about $6 including shipping, to treat 8 gallons which will last me another 4 days, so $1.25 per day. That assumes the PH will stay stable for the full 4 days - which I doubt. This could add a significant amount to the over all grow cost. I am going to do this anyway, but I really really need to kill this algae crap.

3 Likes

After draining the hi PH water in the tank back into the rez, it was at 5.7. Then I dissolved 29 gms of MES into roughly 8 gallons/30 liters. It dissolves easily.

After a good mix, the PH in the rez dropped to 5.0. I slowly added potassium hydroxide (KOH) to the rez to bring it up to 5.5. It seemed to take a lot of the KOH to change the solution compared to usual, so thats good so far.

Unfortunately, I cant compare to @Northern_Loki graphs in the PH thread because I dont know the concentration of my KOH mix. I didnt think I would need to know that when I mixed it up originally, so this is just a feeling on it taking more than normal to shift the PH up.

I also added more chlorine at about 6 PPM.

All of that raised the EC from 1.05 or so to 1.2. Im assuming it was the MES that did most of that.

I should have time early in the morning to check how the PH in the pressurized parts of the system are doing before I have to run off again.

Im really glad Im close to harvest… I have an over whelming desire to kill algae with nuclear bombs…

1 Like

I took a quick look at the roots tonight and most of the fuzzy hairs are gone. Between the algae, the hi PH, the chlorine, and two long almost back to back stretches with no watering at all, Im not that surprised. Still its disappointing - especially given the way some of the leaves look.

I still have pretty good looking hydro roots, but not many fuzzies.

Seeing your images has helped me figure out my def a bit more. That is the exact same leaf issue I have. It has puzzled me for nearly a year now.

I partly wonder if it may be potassium or phosphorous as the symptoms are the same. But then also calcium is a possibility. It is hard to tell as the symptoms are so similar.

If you developed these problems from having a PH that is too high then that sort of excludes Mg, which is even more available at 6.5 than it is at 6.

Potassium and phosphorous are locked out over 6, but calcium is just a bit less available so the former is suggested.

From a google search, it says this is phosphorous def from Agzaar (whoever they are)

I have had this during the time I thought it was Mg.

This is a google image search for potassium def from SensiGarden

Confusingly they are the exact same image…

This one is better for P def

and K def

This helps as now it seems more like K def than P def.

And finally calcium

Of the three, I would put my money on a K def. K is not readily available over 5.3 or under 6.7, which is out of any range I would grow in.

I think it may be time to consider supplementing my nutes with K after about week 3 in flower.

I would love to hear any ideas you have for this def which is the exact same one I have after switching to RO.

1 Like

It’s not important to know. It’s nice to know. As long as the PH is within the buffering region, you’ve got it. You’d only need to know the concentration of the KOH if you are being analytical and/or using it to verify the buffer at the concentration intended is working as expected.

FWIW, I don’t really know if MES reacts with hypochloride in any way.

@5mM MES, the difference needed to move the PH should be quite noticeable. As in, 4x the amount of KOH needed within the buffering region to move the PH.

I don’t know. Are we talking about the EC of the solution already in the system or the EC before it was added? Was the solution cloudy at all prior to the addition of MES? Any precipitation in the system? What was the target EC of the fresh solution?

On the topic sanitizing, look up the Fenton reaction. Not for a live system but for cleaning before the next cycle. Eats organic material like Jeffery Dahmer.

1 Like

Excellent analysis, and thanks for those pics. I have always found it very difficult tying to pin down a symptom. I always seem to have more than one thing going on. Most annoying is that many symptoms are the same for different deficiencies, and its even worse when they use the same pic for two different ones!!

As far as what to do to try to correct, I am not the person to ask. However, it occurs to me that I am using Potassium Hydroxide as PH UP and Phosphoric acid as PH down. I have not been using much if any of the Potassium Hydroxide, due to my PH always going up. I do use the Phosphoric acid a good bit, but maybe not enough?

I have no idea if those two will increase the available potassium or Phosphorus in the correct forms that would be useful to the plant, but I dont know what else to try either. When I re-fill later today I think I will add the MES first, then some Phosphoric acid to drop the PH even lower. That will require even more KOH than I used last time to get back up to 5.5, so the K should be better as well.

Im just shooting in the dark here, so any other ideas are very welcome.

Im disappointed in myself for not measuring the KOH when I made up the solution. I like being able to put numbers on things when doing this type of stuff.

I have not seen any mention in anything Ive read that adding the chlorine shock changes the chemistry in any way - good or bad, but that doesnt mean there couldnt be something going on. Chlorine is very reactive so it would not surprise me if it was messing with something.

4 times seems like its in the ball park at least. For sure, the MES is helping some. At 3AM the rez was still at 5.5 and the tank was at 5.6 and the nozzles were at 5.7 - which was a big improvement, but thats only a couple of hours after I finished re-filling the tank. By 1:30 today, the rez was still 5.5, the tank was 5.8 and the nozzles were at 6.0. Thats better than with no MES and has the nozzles at a much better PH, but its still a bad situation.

The EC in the rez started at 1.05 or so. It didnt look cloudy but the Advanced nutes have always had a slight film on top of the water - like a very light dusting of something. The Mega Crop never did that. Other times when the PH was hi in the rez, I did see signs of precipitation/clouding of the water, but not this time.

Alright!!! Thats exactly the kind of thing I was looking for. Obviously, strong chlorine just isnt killing all of this crap, or its managng ti hide in s=tiny crevices or something. I was planning to do at least a 24 hours soak in strong chlorine again - which I may still do, but I think I will start with this Fenton reaction.

Excellent find!!!

1 Like

The MES is helping a good bit. Its been almost exactly 48 hours since I added the MES and the PH in the tank and the nozzles is staying at 5.8 and 5.9 respectively while the rez is still at 5.5.

Ive been debating increasing the MES to see if the PH at the nozzles will stay any lower, but I think I will just leave it there for a few more days to see if it starts back up again.

Ive considered lowering the PH in the rez even more, but that starts pushing outside the buffer range of the MES, so I dont know how well that would work. Since the PH will almost immediately climb above 5.5 once its in the tank - maybe that would be ok?

I might try that first before adding any more MES.

1 Like

I would. I measure PH at the point it gets fed to the roots and adjust the tank so the PH at the roots is right.

I would make the spray out of the nozzles the right PH if you can, that is all the plants care about at the end of the day. They have no knowledge of your troubles, the PH in the tank, or anything. All they know is what is on their roots.

If some process is raising your PH by 0.5PH between your tank and your nozzles then make your tank 0.5PH lower if you can without precipitation. How low do your nutes say they can go?

Maybe make a few jars with different PH values and see where it precipitates.

2 Likes

I’d try that first before adding additional MES. The three values seem to have more or less stabilized over that 48 hour period.

Don’t get confused on what buffer capacity means. The buffer chemistry itself doesn’t get “consumed”, you can move the PH in and out of the buffering region and the MES is still there and available for ion exchange (assuming nothing is precipitating or eating the MES itself). As long as a there are sufficient cations and anions, the buffering region should look the same even if the PH happens to be outside of the buffering region. It just won’t slow the changes to the PH as readily until the PH enters into the buffering region. Buffer capacity is the size of the chemical “sponge”. The chemical sponge is re-usable. A buffer is not intended for doing the actual PH adjustments (though MES free acid is an acid in this case).

For MC (version 1), during titrations, I didn’t note any immediate precipitation below PH7 or so (down to below 5). Even then, the precipitation that occurred at above PH7 appears mostly soluable when the PH was brought back down. Over a long time frame, however, there does seems to be some hard precipitation in the standard PH range (some sort of slow reaction) but I do not have the data to back that. FWIW, it was noted that citric acid may help counteract this if it does occur. It moves the precipitation to PH9 or so. The buffering thread has some preliminary notes on that.

Ok. Don’t know why the EC changed that much then. MES may have something of a chelating effect and it may increase the solubility of some minerals.

It seems like your tank is some sort of chinesium bioreactor. Which is kinda cool but maybe not in this case.

1 Like

Quick up-date then I have to run again. The combination of extra chlorine shock and MES is working!

The MES alone was able to keep the nozzle PH at 5.9 while the rez was at 5.5. Lowering the PH in the rez to 5.3 dropped the nozzle PH to 5.7 and its stayed at 5.7 for the last 12 hours or so. Woo hoo!

Yeah, thats one of those things that when you finally think of it you go - DUH!! It never occurred to me that the PH would be different at the nozzles than it was in the tank. I ASSumed the PH would be the same all through the hi-pressure parts of the system, and I didnt add the tap to draw samples until just recently.

Ah, thanks for that. I was vaguely wondering about that consumption thing. Glad its not an issue. Of course, the MES gets used when the nutes get used, but thats not the same thing.

I was worried that even with the MES, the PH in the tank would keep rising, but hopefully slower than before, so this is working much better than I had thought it would.

I suspect some of the success is due to the increased chlorine PPM, but I think its mostly the MES. The PH is still going up, so that means the algae is not dead, but maybe the chlorine slowed it down some.

Im going to try dropping the rez PH down another point to 5.2 and see how that goes for another 12-24 hours, then Im going to start raising it up again.

Hopefully, between getting the PH down to a better point and adding extra phosphorus and potassium, the deficiency will at least stop progressing.

I checked more carefully when I topped off the rez and added more MES to the fresh water. Turns out the EC going up is due to me draining nutes back from the tank into the rez. What ever the reactions that are raising the PH, they are also increasing thr EC to some degree. Im going to have to start checking EC at the nozzles as well as PH.

LOL What ever it is I am going to kill it. That Fenton reaction looks like just the thing to kill it AND eat away what ever dead bodies are left over. Im a little worried about the rubber bladder in the tank, but its useless unless I can get this stuff totally out of the system, so Im going to do it anyway.

I checked trichs again, and more of them are milky, but very few amber. Well under 1% at a guess.

2 Likes

Here is an illustration on capacity and what it means as related to the buffer pka values:

The buffer should certainly slow it down. The relatively large and rapid jump in PH between the reservoir and the tank (and then to stay stable) is a bit odd. Only thing I can figure is that there was a remaining quantity of un-buffered solution in the system effectively diluting the buffered solution such that the buffer capacity was largely exceeded initially. Or, maybe it’s the shock that is interfering with how the PH is moving having killed the algae. In changing of several variables, it’s difficult to tell what’s doing what. Clearly, you have to do what you need to do, just a bit ummm, strange on the initial movement of the PH.

1 Like

That helps!

Yeah, I wish I could get away with changing only a single variable at a time, but the plant is in too bad a shape and its obvious that the algae is/was coming back strongly in the pressurized parts of the system, but I don think I have time to wait.

The way this is going down has me puzzled too. I am glad its working this way, but Im having a hard time seeing what the mechanism is.

Its a complex situation with a lot of unknown variables.

This started with 100% Advanced nutes at EC 1.0
Initially, I completely drained the tank back into the rez before adding the MES and adjusting PH. Then I pumped some of that into the tank and then back to the rez. The idea was to have the entire system - low and hi pressure - starting out with the same exact mix with the MES and all starting at the same PH = 5.5.

Within about two hours, the rez = 5.5, the tank was 5.6 and nozzles at 5.7.
Twelve hours later it was Rez= 5.5 Tank=5.8 Nozzles = 6.0

At that point, it was time to re-fill the rez, but Im about out of ADvanced nutes and I really dont like the stuff floating ont he surface or the apparent precipitation swirling in the water, so I left 3 gallons of that in the rez, and added about 8 gallons of RO and Mega Crop to get back to EC 1.0. I added more MES at 5mM again, and did the PH down, followed by more PH up to increase the amount of phosphorus and potassium in the solution - per @MicroDoser analysis of my deficiencies.

Ive also been adding chlorine every top off for several days - increasing up to about 6PPM.

Over the last several days, the PH difference between the rez, tank, and nozzles has been slowly decreasing.

Dropping the rez PH to 5.2 this last time dropped the PH in the tank AND the nozzles down to 5.5! This is the first time the tank and nozzles have been the same sense my last super heavy chlorine treatment.

I can only assume that the steady doses of chlorine have been slowly reducing the amount of algae in the hi pressure parts of the system. That part I can understand.

What seems odd to me is that in between top off or re-fill, when Im making NO changes to the rez or any other pert of the system, the difference in PH between the rez, tank. and nozzles remains constant. In other words, if the rez was at 5.4 and the tank was at 5.6 and the nozzles at 5.7, they stayed at those exact levels until I changed the PH in the rez. I fully expected the PH to slowly climb in the tank and at the nozzles, but it has not.

It seems to much to expect that I was killing off algae at the exact rate necessary to keep the PH from rising, but I cant think of any thing else.

Twelve hours ago, I dropped the rez to 5.2. When I checked again 6 hours later, the nozzles were at 5.6. Then by 10 AM the nozzles were at 5,5. I decided that was long enough and time to raise the PH back up, so I increased the rez PH to 5.4 from 5.2. A few hours later the tank AND the nozzles are at 5.5 while the rez is still at 5.4.

The algae must be getting killed off - finally - by the steady chlorine.

So, I just now drained the tank again, and raised the rez PH from 5.4 to 5.5. I will check again in an hour or so and see what the tank and nozzles are doing. Im going to need to top off the rez again in another day or two, and Id like to swing the PH up some first.

I will be topping off with straight Mega Crop V2 again, but Im going to lower the MES to 2mM from 5mM. With the signs of the algae being less active, I want to see how the lower concentration does.

Im done with AN nutes.

Almost forgot - there was a film that looked like fine dust on the surface of the water with the AN nutes for the last many days. Plus some signs of precipitaion in the mix. After adding the Mega Crop on the re-fill, that all went away.

1 Like