Plants looking a bit sickly, Help please :)

[SeaMaiden]

I like to keep Ca separate from Mg when addressing issues.

HOLY SHIT!!!! I know water hardness in aquarium terms, and your water is almost 15dKH. HOLYFUCKINGSHIT!!! That is some seriously hard water, I am not even joking about that. You could throw in some sand & gravel and get concrete. Holy. Fucking. Shit. That is some hard water.

You've got appreciable levels of NO3 (nitrate), that, even though not exceeding legal limits, which I thought were 40ppm, not 50. If you were keeping fish you would only be able to keep the hardier animals specifically for these nitrate levels. In growing plants, you can use that to your advantage, IMO, if you utilize soil food web critters as much as possible.

I would filter this water, then add back some tap water. I like the Ca:Mg ratio, but that's not to say it's all available.

MAN that's some hard water!

 

[Devilman]

LOL SeaMaiden Yeh it is some damn hard water. Loved the comment about sand and gravel You can probably see now why my tap water EC is usually around 0.4 - 0.5. With regards to the Ca:Mg ratio, whats ideal? Cus it seems I am adding quite a lot of Magne-Cal+ to get rid of the Mg def.

I have thought about getting R/O unit, but finding a decent one at the right price, over here is a bit of a pain in the arse tbh.

 

[Devilman]

Update time..

I've been adding some Magne-Cal+ to the mix in increasing amounts to try and combat what seems to be the MG def discussed previously, but so far I still seem to be having some problems.

Some plants still show a distinct pale perimeter to the leaves as can be seen in the 2 pics below.



I recently read somewhere that excessive amounts of Ca can interfere with the uptake of Mg, could it be possible given my water quality, hardness etc.. that it could be causing a problem? As I see it, giving them a cal/mg combination additive could just aggravate the problem even more, since I think they typically have more Ca than Mg anyway, upsetting the balance even more?


I seem to be having a hard time dialing in on the right feeding schedule, I recently noticed I seem to be getting noticeably slower growth rates and leaf discoloration on some plants I have in small pots of clay pebbles, vs ones I have sat in a couple of 3inch R/W cubes. All 4 were taken at the same and potted / cubed up at the same time. (Forgive a few of the odd shaped leaves, they were from reveg)



You can clearly see from the pics, the 2 plants that are in pebbles seem much less vigorous and have some lowers discoloring etc.



Again this last pic is of another couple of plants I have in small pots in pebbles, and again both have the same signs of yellowing, deficiency and so forth, which leads me to think its more a problem with uptake, than availability, or maybe feeding cycle?

For reference, the first 2 pics of the "MG Def plants" they are in 6inch pots and the plants are approx 5-6 inches tall. The pics of the plants in small pots, they are only little 3.5inch starter pots and the plants are maybe 4" tall, while the ones in rockwool are maybe only a couple of inches taller, are clearly much more vigorous.

Initially I was concerned that I didnt want to flood the small plants too often, as they were cloned in peat pellets and that stuff holds water so long compared to the pebbles, I was concerned about saturating it and having stem-rot or just limited root growth.

Do you think the problem could be that I need to feed less (lower EC) but water more (more flood cycles) on these small pots? Or could the problem be the peat pellet they were cloned in takes up nearly half the volume of the pot, and holds a lot more water, that the 2 are just incompatible?

Any help or suggestions would be appreciated, since seeing the difference in growth-rate between the plants in pebbles vs rockwool, its really hit home that something isnt right with my hydro setup, Its meant to be a fast growth method, but I am just not seeing it yet.

Thanks all.

 

[SeaMaiden]

The plants in the pebbles must be treated differently than those in soil, and they do look hungry, I agree.

But, back to the Mg issue, it's got a lot to do with the *form* of Mg and whether it's available. If it's tied to a carbonate molecule (CO3) then it's more difficult to 'break' apart, requires acids or strong microbial action, if you will. So, if you're adding back Ca & Mg, the form itself is important. If it's CaCO3 or MgCO3 (calcium and magnesium carbonate, respectively), you're right, it could very well compound the problem. If it's in another form then there should not be such a problem.

SUPER quick fix for the Mg- is to use MgSO4 (Epsom salt), which will also provide a bit extra S (sulfur).

While I haven't grown using hydroton or rockwool, as I understand it, both have their own feeding requirements particular to each media. First I would look to pH requirements and compare those to the parameters you're maintaining, may need some tweaking.

 

[Devilman]

Thanks Seamaiden. What do you think on the possible problem that at such a small size / age, the peat pellet they were cloned in, holds far more water than the clay pebbles, possibly preventing a flood cycle as often as would normally be needed, for fear of stem-rot or over-saturating the pellet they started in?

I realise hydro setups are maintained and fed / watered very differently to soil, and often media to media, as some retain water far more than others (R/W vs pebbles) and while I have never grown in soil so can't speak much to that, I have done a bit with pebbles / RW cubes before and Im more trying to figure out why I'm not getting the growth I should.

Whats the prefered method of cloning and such for a typical pebble grow? clone in Rapid Rooter / Root Riots then into 3" R/W and finally into bigger pots with pebbles, or is it better to drop a small clone, with as little "cloning medium" as possible straight into pebbles and just irrigate very regularly, to avoid the "wet zone / dry zone" difference between the pebbles and the Rockwool cube (or Rooter plug / Peat Pellet)

By the way, when you say they look hungry, do you think they would benefit from more frequent flooding? since my E.C is at a reasonable level (around 1.5EC) so perhaps they are just not seeing food regularly enough?

Thanks

 

[TheArchitect]

Hey devil, saw your other post, I'd be glad to help to my abilities.


Looking at all the parameters you've provided, I'd wager a fair sum that your problem is almost 100% source water related.

190 mg/l of carbonates is off the charts.

What's happening in the rootzone is that the high level of carbonates are fighting for the free acid floating around in the rhizosphere. This battle is lost by the acids over time when carbonate levels are high, as it will progressively raise ph to levels which cause all sorts of lockout, primarily mg, because the carbonates come in the ca form.

No you have a few options, like 2 really. 3 if you want to soften your house water.

Option one: acid neutralization; add nitric acid in veg, and phosphoric acid in flower, until your tap water settles at 4.2 ph. You can then add your nutrients.

Option two: reverse osmosis(preferred method); pretty self explanatory.

Option three: water softener; again self explanatory, though if you go this route youd probably wat an ro filter, as the softeners work by swapping ca for na. This will make your ro last longer though as the sodium is easier on the filter than calcium carbonate.


Hope that helps.


Ps 2ec will be too hot if you go the reverse osmosis route.

 

[Devilman]

Architect, Thanks for stopping by, appreciate your input,

My water hardness is pretty off the charts indeed, I have been considering the R/O route for a while, but possibly mixing it 50/50 or 75/25 with my tap, just to gain some of the trace minerals and such in there, as the nutes I am using dont really give any indication of ratios or macros and such.

Do you think more regular flooding intervals may at least help alleviate the problem, by swapping out the fluids in the rootzone, hopefully re-balancing it more often? I'm not getting drastic PH swings in the res but I guess in such small pots, that its much easier for a PH rise due to excessive carbonates?

I'm looking to get hold of some epsom salts to use in the res, in place of the Magne-Cal I am currently using, as it seems adding more Ca (especially if its in the form of CaCO3 is just counter-productive) and they just need a more balanced ratio of Ca to Mg than they currently are getting.

Is there any rough guidelines as to typical ppm amounts of various elements the plants may use? Obviously I realise things like N,P,K are going to change drastically between veg and flower and also with plant size, but I have seen it wrote a few times that a good "average" for Mg is 30-50ppm/L which should be 30-50mg/L I believe? if so, my water source has only 11ppm/L or so of Mg, coupled with very high levels of CaCO3, so perhaps Its this ratio I need to re-balance with some Epsom Salts?

Thanks

 

[Devilman]

Double Post

 

[TheArchitect]

Unfourtunately flooding more wont help.

The reason is because, while that might help regulate ph, it doesn't help ca:mg ratio, actually as you even point out, as the carbonates are neutralized they free up the ca exacerbating the mg lockout by increasing ca:mg.

Ideally, you'd just get the ro, and you'd be fine.

But if you want I can try and help figure out another method of attack, to work with your water.


You could add Epsom, which when dissolved gives free mg and sulfuric acid which will help nuetralize the carbonate and bring your ca:mg inline (preferably 1.5 or 1.75, ie 100 ppm ca 50-70 ppm mg, these aren't set in stone numbers just a round number example)

Now, concentration could be a problem, it's hard to overdose on ca and mg( as long as ratios are right) but not impossible, so the epsom route may not work. You may have to find a hard water nutrient that has lower calcium and increased acids.

 

[SeaMaiden]

Thanks Seamaiden. What do you think on the possible problem that at such a small size / age, the peat pellet they were cloned in, holds far more water than the clay pebbles, possibly preventing a flood cycle as often as would normally be needed, for fear of stem-rot or over-saturating the pellet they started in?

I realise hydro setups are maintained and fed / watered very differently to soil, and often media to media, as some retain water far more than others (R/W vs pebbles) and while I have never grown in soil so can't speak much to that, I have done a bit with pebbles / RW cubes before and Im more trying to figure out why I'm not getting the growth I should.

Whats the prefered method of cloning and such for a typical pebble grow? clone in Rapid Rooter / Root Riots then into 3" R/W and finally into bigger pots with pebbles, or is it better to drop a small clone, with as little "cloning medium" as possible straight into pebbles and just irrigate very regularly, to avoid the "wet zone / dry zone" difference between the pebbles and the Rockwool cube (or Rooter plug / Peat Pellet)

By the way, when you say they look hungry, do you think they would benefit from more frequent flooding? since my E.C is at a reasonable level (around 1.5EC) so perhaps they are just not seeing food regularly enough?

Thanks

Devilman, I wish I could answer your questions re: clay pebbles and rockwool, but I don't feel qualified since I've never worked with either media. If you were using perlite, coco coir or soil, then we could talk. I used the peat pucks for the first time last year, and hated them, got a high failure rate with EVERYTHING--veggies and cannabis.

Best I can suggest is to figure out one problem, whatever you feel is the most pressing problem, and then if other problems remain address those, one at a time. I say this because it may be several issues working around, against, within or in combination of each other.

However, the hungry plants, my approach is to feed more lightly, but also more often, so what you propose is very much along the lines of how I would approach it were I in your shoes. I'm going to read what others have posted after this before I say anything else, though.

 

[Devilman]

Also, A few questions regarding nutrients and suppliments.

I see you said about using Nitric acid in veg and Phosphoric acid in flower, I see the benefits, but thus far I have always used Phosphoric acid PH-Down in both veg and flower, is this a problem? I realise nitric acid will give N which is usefull in veg, however strangely even when using phosphoric acid during veg, as you can see from the pics I still get some signs of P-def.

Is there a specific order to stick to when mixing up? Ive seen a few threads that say Silica sources should always be added first (I do not currently use these), then Ca and Mg sources and finally base nutrients and then boosters, finally PH'ing at the end.

I have to confess up until now I had been always adding base nutrients, then additives (including Magne-Cal+) and finally PH'ing with Phosphoric acid. Could this have been causing an issue, or "binding up" certain elements making them unavailable due to an incorrect mixing order?

You mention about PH'ing the water down to 4.2 before adding anything, is this more of an arbritrary number that varies based on the starting PH / Carbonate count, or a reasonable starting point regardless? My tapwater typically comes out at anything from 7.5 - 7.8 and once it has sat bubbling for a while, rises over 8.0 which may need a lot of PH-Down to pull it that low to start. I Also run hardwater nutrients which are usually more acidic than normal, so perhaps 4.2 is too low to start?


Is it worth testing in a small volume (say 1gal) to find what starting-point PH I want to go down to before adding anything? and would using Phosphoric acid for this still be acceptable in veg, or better to switch to nitric acid for veg?

A lot of questions I know lol, but any help is usefull, Thanks.

 

[TheArchitect]

Also, A few questions regarding nutrients and suppliments.

I see you said about using Nitric acid in veg and Phosphoric acid in flower, I see the benefits, but thus far I have always used Phosphoric acid PH-Down in both veg and flower, is this a problem? I realise nitric acid will give N which is usefull in veg, however strangely even when using phosphoric acid during veg, as you can see from the pics I still get some signs of P-def.

You can use any ph down whenever, I just like nitric in veg and phosphoric or sulfuric in flower.

The purpling stems is magnesium, not phosphorus, I have no conclusive proof, but lots of experience, and not once have I had P deficiencies, magnesium and calcium are maybe the two most frequent problems.

Is there a specific order to stick to when mixing up? Ive seen a few threads that say Silica sources should always be added first (I do not currently use these), then Ca and Mg sources and finally base nutrients and then boosters, finally PH'ing at the end

I have to confess up until now I had been always adding base nutrients, then additives (including Magne-Cal+) and finally PH'ing with Phosphoric acid. Could this have been causing an issue, or "binding up" certain elements making them unavailable due to an incorrect mixing order?

Yes silica has to go first, past that I've never really had a problem, I use jr peters and mix base, Epsom, calnit in that order.

You mention about PH'ing the water down to 4.2 before adding anything, is this more of an arbritrary number that varies based on the starting PH / Carbonate count, or a reasonable starting point regardless? My tapwater typically comes out at anything from 7.5 - 7.8 and once it has sat bubbling for a while, rises over 8.0 which may need a lot of PH-Down to pull it that low to start. I Also run hardwater nutrients which are usually more acidic than normal, so perhaps 4.2 is too low to start?

I'll try and find the article, but no 4.2 is not arbitrary, when you bring the ph down that low and get it to stabalize there, all the carbonates have been nuetralized.

Now, if you do that you need to compensate in your mix, ie you have 190mg/l caco3 which when nuetralized will leave you with ~75 mg/l ca. (caco3 is 40% ca by weight)

Your water is likely too hard for hard water nutrients, so they will offer little benefit. What I would do personally is get an ro filter, or go to a raw salt mix like jr peters, use nitric to decarbonate(which will compensate for reduced calnit application), add Epsom, and cut the cal nit down to keep calcium at appropriate levels.

Is it worth testing in a small volume (say 1gal) to find what starting-point PH I want to go down to before adding anything? and would using Phosphoric acid for this still be acceptable in veg, or better to switch to nitric acid for veg?

A lot of questions I know lol, but any help is usefull, Thanks.

What would be a good test is a sample titration, iow, see how much acid you need to get one gallon down to 4.2 ph stable, en go from there.


Hope this helps

 

[Devilman]

Hi, another update time...

I finally got some epsom salts arrive, may start introducing them shortly, although as I look around my "garden" I notice that only a couple of the plants (the origional ones pictured) show the "deficiency" at all.

Making me wonder if its more a pest issue and less a nute issue, since only a couple of plants are affected?

I have been adding back nothing but tapwater for nearly a week now and still the E.C. has barely dropped, which I guess could be a pretty strong sign that I was feeding them too hot as well, Going to keep diluting with tapwater add-backs until I see a point where E.C. clearly drops after a feed (or a few feeds) and hopefully will be a bit closer to the plants eating habits then.

I have also been looking into a few of the various preventative / pest treatment measures, I have a few with (I think) springtails and a few fungus gnats that appear in the water after feeding, but also I'm interested in finding the right preventative measures. I've read plenty of people with different preventative treatment plans, but some of them look seriously over-complicated or a case of "lets throw everything at them and hope its ok"

I was thinking about picking up some "Gnat-off" and maybe some Bayer Fruit & Veg to use as a preventative / regular treatment during veg to hopefully keep pests at bay, would you recommend these products, or any others you prefer / would add to the mix? I'm a UK grower so some of the stuff you peeps have over in the US we can't get here unfortunatly.

Do you see there would be any issue using things like Gnat-off and Bayer at the same time? I mean is it possible the imid in the bayer might neutralize the gnat-off or anything odd?

Also is it preferred introduce them to the hydro res and just let it cycle, or to dunk / soak each plant separately for a few minutes in an appropriate bucket of solution, then return them to the system without adding "too much" of Gnat-off or Bayer into the res?

Cheers.


*Edit* Ialso, on the subject of "pre-PHing" down to 4.2 to neutralize carbonates, how does this still work when using our nutrient lines? typically they can drop PH fairly low by themselves at times, so obviously If I were to PH down to 4.2 to start with, I dont really see how I can then add any nutes, before the PH plummets and the solution becomes like battery acid.

Any tips / thoughts / suggestions welcome

 

[TheArchitect]

I was thinking about picking up some "Gnat-off" and maybe some Bayer Fruit & Veg to use as a preventative / regular treatment during veg to hopefully keep pests at bay, would you recommend these products, or any others you prefer / would add to the mix? I'm a UK grower so some of the stuff you peeps have over in the US we can't get here unfortunatly.

Do you see there would be any issue using things like Gnat-off and Bayer at the same time? I mean is it possible the imid in the bayer might neutralize the gnat-off or anything odd?

Also is it preferred introduce them to the hydro res and just let it cycle, or to dunk / soak each plant separately for a few minutes in an appropriate bucket of solution, then return them to the system without adding "too much" of Gnat-off or Bayer into the res?

Cheers.

the two best gnat control products are gnatrol and botanigaurd.

both are fine to use up to harvest.

gnatrol is concentrated BTi (mosquito dunks on steroids)

botanigaurd is similar but a different bacteria..

*Edit* Ialso, on the subject of "pre-PHing" down to 4.2 to neutralize carbonates, how does this still work when using our nutrient lines? typically they can drop PH fairly low by themselves at times, so obviously If I were to PH down to 4.2 to start with, I dont really see how I can then add any nutes, before the PH plummets and the solution becomes like battery acid.

Any tips / thoughts / suggestions welcome

i wouldnt worry about the ph being too low after you reduce carbonate load.

low ph doesnt necessarily beget problems, alkalinity is more important.

if you want you could add silica and that will raise it up.

 

[Devilman]

Thanks for the reply Architect, with regard to the Gnat-off, looks like its basically the same as Gnatrol, just one you can get in the UK. (Gnatrol isnt available here)

Gnat-off also contains Bacillus Thuringiensis, so should do the job fine, just unsure whether its better to run it in the res full-time, or just dunk / soak the plants in a batch made up once a week or something...

Same goes for the Bayer, is it better to add it to the res perhaps once every week, throughout veg (and maybe just a week or 2 into flower?) or run them fulltime. I can see that running them fulltime could build up immunity to them, which is also a concern.

With regard to carbonate neutralization, could it be possible to drop PH say, part of the way to 4.2, to allow the use of nutes without PH dropping to low, or is that not really how it works?

Im guessing that by neutralizing all carbonate in the water, it would have a very similar response to PH changes as R/O water does, as they both effectively have no akalinity / carbonate hardness left to buffer PH changes?

Could I perhaps make a batch up to 4.2 to neutralize it, then mix it back with some amount of my tapwater to both raise the PH back up and add some level of alkalinity to buffer PH changes and allow nutes to be used without PH dropping too low?

If using Silica to raise PH, would it be better to add it first, then pull the PH down, or would it still be needed to PH to 4.2 first for neutralization, then add silica to raise PH to a more suitable level for nutes to be added?

 

[TheArchitect]

Thanks for the reply Architect, with regard to the Gnat-off, looks like its basically the same as Gnatrol, just one you can get in the UK. (Gnatrol isnt available here)

Gnat-off also contains Bacillus Thuringiensis, so should do the job fine, just unsure whether its better to run it in the res full-time, or just dunk / soak the plants in a batch made up once a week or something...

oh, ok.

yea run it in your res, i ran it in rdwc and e&f, though it does leave a little sludge.

Same goes for the Bayer, is it better to add it to the res perhaps once every week, throughout veg (and maybe just a week or 2 into flower?) or run them fulltime. I can see that running them fulltime could build up immunity to them, which is also a concern.

bayer you should apply only once, and really unless you have aphids, i wouldnt use it, its systemic.

you could use it on moms though.

With regard to carbonate neutralization, could it be possible to drop PH say, part of the way to 4.2, to allow the use of nutes without PH dropping to low, or is that not really how it works?

you can try, im not too sure. if you do, whatever ph point you decide on, give it time to stabalize before you mix nute.

so if you choose 5.4 as a target, get it there and then maintain it for a day to be sure it isnt going to keep climbing back up.

Im guessing that by neutralizing all carbonate in the water, it would have a very similar response to PH changes as R/O water does, as they both effectively have no akalinity / carbonate hardness left to buffer PH changes?

pretty much....

Could I perhaps make a batch up to 4.2 to neutralize it, then mix it back with some amount of my tapwater to both raise the PH back up and add some level of alkalinity to buffer PH changes and allow nutes to be used without PH dropping too low?

this is what i would do if your that worried about the ph. but ive had healthy plants in ph of 3-4 before....

If using Silica to raise PH, would it be better to add it first, then pull the PH down, or would it still be needed to PH to 4.2 first for neutralization, then add silica to raise PH to a more suitable level for nutes to be added?

ph to 4.2, then add silica, then add nutrients.

 

[Devilman]

oh, ok.

yea run it in your res, i ran it in rdwc and e&f, though it does leave a little sludge.

How often would you add it / reintroduce it to the res? or would you just add a specific volume per L, the same as you would other additives?

bayer you should apply only once, and really unless you have aphids, i wouldnt use it, its systemic.

you could use it on moms though.

Well, was only planning to use in veg, one of the reasons being last couple of times I've had issues with Scale insects and since I both live in the country and have pets, I dont think I could keep them away just being careful. I have of course cleaned everythin with a bleach solution between runs etc, but still they seem to re-appear, so figured a hit or 2 of the Bayer should get rid of them.

Am I right in asuming its the Bayer Fruit, Citrus and Veg I'm looking for, Ive seen another but I think thats only for hardier plants / trees, or is it purely based on the levels of Imid in them?

With regard to the water, I may try seeing how things may fair if I try lowering PH to say, PH6 or something, then adding nutes etc.. (since I'm still using HW nutes, they are a bit more acidic)

Considering my Ca / Mg levels in the water, do you have a rough idea how much epsom I should think about adding, to raise the mg/L from the 10 or so I have, to a more reasonable level in balance with my Ca?

My water quality report says I have average of 90mg/L of Ca, but almost 190mg/L of CaCO3, which should I be looking at more to base my Mg levels from? Obviously one would result in 45 - 70mg/L and the other would be a lot more (95 - 145 mg/L), or is this likely to vary based upon how much CaCO3 I manage to effectively neutralize by "Pre-PHing"

If I go that route of "Pre-Phing" to a certain point to help neutralize carbonate, some of that is going to return as "pure Ca" (ref. you said CaCO3 is 40% Ca by weight and is left behind after neutralization?) so its going to make finding an ideal ratio of Mg to add rather difficult?

I appreciate the help

 

[SeaMaiden]

Devilman, it needs to specifically be Bacillus thuringiensis subspecies israelensis. Most products with Bt are actually Btk (Bacillus thuringiensis kurstaki) and they are *not* effective against fungus gnats.

I believe Botanigard is a completely different animal, it's a fungus, Beaureria barsirtna Strain GHA. I'd have to double check my literature, but I'm willing to say with 99% certainty that's what that it is, not any Bt spp.

 

[Devilman]

Well, the Gnat-off we can get over here, which only says it contains Bacillus Thuringiensis, not sure about the sub-species, however it does say its made for fungus gnats, so I guess it must be BTi ?

 

[SeaMaiden]

We shall see!