Sm-90 in place of hydroguard


Does anyone have any experience with using sm-90 instead of hydroguard to keep an optimal root environment in DWC. Sm-90 is advertised as a foliar spray but I’ve read about people using it in the reservoir like hydroguard.

From what Ive been reading on sm-90 is that it and hydroguard cannot be used together, kinda like 3% h²o² and hydroguard.

I was curious if anyone had any experience using sm-90 in this manner and if it works, can it and 3% h2o2 be used in conjunction with each other.


@Hogmaster @latewood @garrigan65 @bob31
As I have no experience with these nutrients, someone else will at least have input. @TDubWilly


Sorry not me!



SM-90 is a wetting agent but I could see some using it in hydro to make it easier to keep roots moistened


@Donaldj The back of the bottle says to put 3-5ml per gallon into your reservoir for hydroponic setups. It’s a sterile solution unlike hydroguard.

I’ll get a pic of the back of the bottle and put it up



I don’t think I have to worry about keeping roots moist if they are sitting in water do I?

This was the directions on the bottle…
Prepared from natural plant oils, Nutrilife SM-90 may be used as a wetting agent in both field and hydroponic applications. Encourages new root growth and can be applied as a foliar spray or directly in reservoirs with nutrient solutions. 100% bio-degradable and non-toxic to humans, animals and plants.

• Improves spray coverage in soil and on plants
• Lengthens contact and control of sprays
• Increases the speed of moisture penetration in soils and growing media
• Reduces surface tension of spray nozzles and irrigation systems


Hydroponics Systems: Apply 2-3 ml to each gallon of nutrient solution on a weekly basis or whenever solutions are replaced.

Foliar Sprays: Dilute 1 part with 5 parts water to prepare a foliar spray. May be repeated every 3 days for up to 3 spray applications.

Grower’s Tip:
**When this product is added in small quantities directly to plant nutrient solutions, new root growth emerges. Treated plants develop greater root area, root runs and exhibit generally healthier root

I just didn’t know why a wetting agent would also be used in a hydroponic reservoir unless it was able to fight root rot in some way. Would it be beneficial to roots in some way if they were extra moist?

Hydroguard has been smelling bad lately, roots look fine, reservoir is just smelly.


sm90 was first thing hydro store sold me when I asked about hydro root rot. it can be used with hydroguard as it will enhance the microbe.



See, I have read the opposite, that sm90 will kill “beneficial bacteria” from the hydro guard


I stand corrected, guy at hydro store lied to me too. Might explain a lot…


Lol, well I don’t know brother, I’m more just asking and seeing what others know about it, you don’t stand corrected, I was just stating what I’ve read :grinning:
I appreciate the response


wetting agents are emulsifiers and basically would by nature keep roots cleaner they reduce surface tension of water allowing it to rinse and bond better to minerals and contaminates alike. This would also increase surface area contact of solution (thinner film of water) on roots in turn allowing better o2 absorbing qualities more air to roots even though they are wetter :wink: This may be a win win if you think about it?
I am just guessing the rational of suggestion and theory behind it but would be my thought with fresh mind and few cups of coffee into me :slight_smile:


Lol, right on DJ, thank you


Myself I woke up this morning with a 3 week old rqs critical that caught root rot overnight and what I did is flushed the system with pH water and added 10 more mL of hydroguard and within 3 days it should be gone