Does anyone use extra nutrients?

I just started my first “real” grow since getting my unit. I have a lingering question, especially since I’m a novice grower. Does anyone know if you can use other nutrients or additives in conjunction with or in place of the bar nutrients they give you. Just wondering, I woulds like to grow the best bud possible.


There are all sorts of posts floating around about people using this, people using that, I had the same burning question so I asked @Dani.

The response she gave me, sorry it’s not verbatim, but per the team they recommend only adding hydroguard along with your Grobo nutrients to prevent root rot.

Hope that helps! :grin:


If its your first grow in the grobo, I wouldn’t do any added nutes other than hydroguard or a similar product. But yes, you can use a whole range of nutes. The important thing to know when adding anything extra is there has to be a correct sequence for it to work properly. When/if you add extra nutes, always let the nutes from the machine dispense first. Give them 30 min or so to mix in the water, then add other nutes with a syringe by plunging into the grobo by lifting the lid. Hydroguard always goes last.


From what I’ve been reading, a few pros agree that ‘big bud’ and ‘flawless finish’ are the two extras to use at the end of the grow outside of hydroguard if you are going to use anything else. Ive personally only used big bud and hydroguard so I cant speak to anything else.


How did those 2 work for you. Did you notice any difference as opposed to when you didn’t use it?

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One thing to underline with additional nutrients, is that as much as they can help they can also hurt. I recently caused a nutrient lockout in my last grow from mixing an additive improperly, for example, which resulted in complications and might’ve actually reduced my yield (and quality) somewhat.

It’s generally recommended to try growing one or two plants to completion before modifying many of the parameters (like inputs/feed) in order to get the defaults dialed-in (and confirmed to be good for you) and then make some changes/tweaks from there.


In addition to Hydroguard, I use these right up until flush:
SLF 100
(May try some Hygrozyme)

During bloom I add:
Bud Candy
Big Bud

For flush I plan on adding:
Flawless Finish

EDIT: Probably won’t bother using Bud Candy next grow.


@VermontGrobo @vegetato

Are yous guys doing any manual pH balancing after adding extra nutes ?

I have the chiller running so my reservoir is a bit diluted and have thought of juicin’ a bit near the end.

@HelmutVonPants, I use a different set of base nutrients (AN ph-perfect 3-part set) but still use grobo ph up/down. In addition to the base set is GH Armor Si and AN Big Bud.

Just now when doing a drain/fill I just mixed the following into my fill bucket, in this order:

  • 5.5L of room temp water (~68°F)
  • 0.13g of AN Big Bud powder (stir for few minutes)
  • 3mL of GH Armor Si (stir for few minutes)
  • 20mL of AN Sensi Cal Mag Xtra (stir for a minute)
  • 20mL of AN Micro (stir for a minute)
  • 20mL of AN Grow (stir for a minute)
  • 20mL of AN Bloom (stir for a minute)
  • 5.5L of water from fridge (~54°F)

When all of that was done the pH lands around 5.9-6.1. I haven’t even manually measured the pH to verify in quite some time because every time I did in the past it was always correct. The grobo probe is how I verify that, whether or not I notice it dose any pH up/down afterward.

I’d like to get away from the base AN set and other additives and instead make everything from powder/salts myself. Have been eying the Canna brand stuff as a full-suite to try replacing most of that with for the meantime, but (so far) have grown accustomed to the pH balancing aspect of the AN set.

The reason I’m using AN right now is mostly just laziness (or convenience, however you look at it). I had it on hand from an outdoor grow and decided to try it when things weren’t working well for me at first in the grobo. For the past few grows, I’ve been feeding the plants a minimum of nutrients (1/4 to 1/8th what bottle recommends) and letting my water changes ride past their due dates, and this stuff seems to keep pH in check, even through my mishandling of all that. Lately, the grobo barely ever doses any pH up/down at all – I recently noticed one little shot missing from one of the bottles over the course of a 6-8 week period.

I’d still like to get away from not knowing exactly what’s in those nutrients (or the “magic” behind the ph balancing), and have been trying to find a lineup produced by a :canada: company instead. That’s more of a personal preference than due to any problem with the AN products, though.

TLDR; I use specific set of nutes to do the pH balancing (seems to work for me)

Edit: this better shows what I mean by riding past water change due dates, I had to do this to keep track of just how long it’d been since the last one :rofl:


@vegetato awesome breakdown thanks !!

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Dude thank you for the awesome information. I will put it to use.

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Hey! Sorry for the delayed response… i am only on my 2nd grow and its a different strain so its hard to say how much the big bud and hydroguard helped. After this grow, I’m going to grow my 1st grow again. I didnt use anything extra with it, so I will be able to see what difference the added nutes make. I will say that my current grow with the big bud is very sticky and dank smelling but I dont know how much of it is related to strain/genetics vs added nutes.


Hi Vegetato,
I was wondering when do you cut / stop adding armor si. I currently running 1 ml for 3 gallons. Didn’t want to over do it. Any hoot. I notice some people run silica until flush and others cut between flower week 3 or 4. Was wondering what you would recommend.
Thanks in advance
Happy Growing!

I bring it in gradually around week 3-4.

Start it off really weak adding a total of 1ml to the res around week 3 and work my way up to 3ml over the course of a month, and I stop using it shortly after the switch to flower.

It usually ends up being dosed something like: 1ml, 1ml, 2ml, 2ml, 2ml, 3ml, 3ml, none

The reasons I’ve seen posted elsewhere as why not to use it past vegetation and into flower are:

  • it makes the buds harder (physically, like stiff/hard)
  • it makes the buds burn differently (hotter/harsher)

On an earlier grow when I did use it through flower but not in flush the buds did get kind of stiff, so I looked into what made that happen and adjusted my silica input accordingly.


Thanks Vegetato, goes right along with all the info I have read regarding cutting silica. Sounds like you got it dialed in pretty good. Appreciate the feedback :+1:t4:


Great Question! Was just wondering this myself if its possible or not…