Sure to Grow® Technology Overview

Nutrient Dosing

Bucket Systems (Including the CAP Ebb and Grow)

Aeroponic Systems (Including the Aeroflo (GH) series and most cloner systems)

Flood and Drain

Super Modified Raft Systems

Top Water (including Slabs)


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Sure to Grow® Technology Overview

Can Sure To Grow hydroponic inserts and Hail products be overwatered?

Yes. All hydroponic media, regardless of construction and composition, can be overwatered, especially during early veg and late bloom.

STG Storm and Hail watering protocol

During early vegetative growth weeks 1-3 (i.e. newly rooted clones, and seedling starts) Total watering time should not exceed 30 minutes per day Total watering intervals should not exceed 2

During mid to late vegetative growth weeks 4-6 (established plants with juvenile to mature root systems)
Total watering time should not exceed 60 minutes per day
Total watering intervals should not exceed 6

During early to mid bloom weeks 7-9 (established plants with fully developed root systems)
Total watering time should not exceed 45 minutes per day with some plants benefiting from even less
Total watering interval should not exceed 4

During late bloom weeks 10-? (established plants in survival mode due to high stress)
Total watering time should start at 45 minutes and gradually be decreased until plants have finished
Total watering intervals should not exceed 3 and most would benefit from 2 or possibly 1

What is STG made from?

STG’s hydroponic media is made from PETE1 — the most recycled, food grade safe plastic in the world. It does not leach and requires less energy to produce and ship than any other commercially available media option.

What is PET1 (or PETE1)?

PET1 can be semi-rigid to rigid, depending on its thickness, and is very lightweight. It is strong and impact-resistant. It is naturally colorless with high transparency.
While most thermoplastics can, in principle, be recycled, PET1 bottle recycling is more practical than many other plastic applications. The primary reason is that plastic carbonated soft drink bottles and water bottles are almost exclusively PET1, which makes them more easily identifiable in a recycle stream. PET1 has a resin identification code of 1. One of the uses for a recycled PET1 bottle is for the manufacture of polar fleece material. It can also make fiber for polyester products.
Because of the recyclability of PET1 and the relative abundance of post-consumer waste in the form of bottles, PET1 is rapidly gaining market share as a carpet fiber. More than 17 billion bottles have been recycled into carpet fiber. PET1, as with many plastics, is also an excellent candidate for thermal disposal (incineration), as it is composed of carbon, hydrogen, and oxygen, with only trace amounts of catalyst elements (but no sulphur). PET1 has the energy content of soft coal.

Is PET1 safe to use in hydroponic systems?

Absolutely! STG is inert, pH neutral and sterile. Our product does not shed or breakdown in your system nor does it impart anything to your hydroponic crops. Finally, STG is BPA free.

Is STG biodegradable?

PETE1 is not biodegradable but is highly recyclable and can be cleanly burned in a biomass furnace with a thermal value similar to soft coal.

Can STG be recycled?

YES! We suggest leaving only the root mass behind and allowing the substrate to completely dry out first.

Can STG be reused?

We do not encourage growers to reuse STG. This recommendation is a result of extensive research that has led us to the conclusion that the vast majority of chronic root borne disease problems associated with indoor gardening are the result of internally recycled media.

Is it pH neutral?

Yes, this is a function of its use in the food packaging industry.

Will STG support a large flowering plant?

We have successfully performed hydroponic vegetable gardening indoors with a variety of crops from 3.5 to 3.75 feet without any staking or trellising. We do, however, recommend that if you intend to grow plant in excess of four feet, staking or trellising may be required.

Does STG wick or exhibit capillarity?

The short answer is no, but there is a small rise in column when STG is initially introduced to the system. This is likely a result of weak cohesive forces driven by our patented cluster technology.

How much water will STG hold?

Sure To Grow will hold 82 percent of its total volume when saturated.

How much air will STG retain when saturated?

Approximately 18 percent of the total volume is occupied by ambient gas when saturated.

How often should I water?

This is dependent upon the crop you are cultivating. If you are growing sedum, your watering schedule would be greatly reduced to someone who may have a large “mortgage lifter” hydroponic tomato specimen in full bloom. My suggestion is to increase your watering frequency until you begin to see signs of “overwatering stress”. These signs are different for different crops, however almost all plants exhibit yellowing of the leaves when exposed to too much water. Once you have reached this threshold, dial back your frequency until the yellowing subsides. Once you have the frequency established, you can begin to tweak the duration. Remember, shorter duration and increased frequency is optimum for plant growth. Just like humans, plants operate best when fed many small meals instead of the traditional “feast or famine” approach used by many growers.

What kind of water retention / residence time can I expect?

Water retention is similar to that of Rockwool. However, unlike Rockwool, STG uses weak physical forces to retain water. Therefore, it is exceptionally willing to release stale nutrients with every flood cycle, ensuring your plants are bathed in a fresh, oxygen rich solution.

What crops are best suited for STG?

We have yet to come across a terrestrial plant that cannot be grown in STG. Whether you’re trying to grow hydroponic strawberries or growing hydroponic herbs, the only limit is your imagination.

Does STG work with all hydroponic setups?

We have observed phenomenal success in all hydroponic systems we have tested with the exception of the “Waterfarm” model. This system poses a challenge for us due to its design. In past trials, decreased performance was realized.

What sizes do your hydroponic grow products come in?

We have sizes that fit nearly all of the most popular net pots and buckets as well as an entire line dedicated to shapes and sizes that are considered industry standards. We also offer our product in a loose fill form that can be used conveniently in any size or shape container.


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Nutrient Dosing

How should I dose my reservoir?

One of the most critically overlooked components of dosing is initial water quality. R.O. (Reverse Osmosis) water is currently the benchmark standard for hobby hydroponic systems and provides the grower with a relatively standardized baseline to operate from. If you do not have access to a R.O. tap, don’t panic. Tap water with a ppm value less than 180 can be left out overnight to “off gas” or actively aerated to accelerate the process. Once the water is prepared, a pH value should be obtained using a reliable method. For best results, the water should be adjusted to 5.8 to 6.3. This can be done easily using a standardized pH up or pH down solution. For best results, add the pH adjuster concentrate to a liter of water first and then add that volume to the reservoir to avoid wild fluctuations and nutrient lockout. Once your water has been adjusted add the base nutrients and additives as directed by the label. It is important to follow these directions carefully due to the complex interactions that must take place to unlock the chelated constituents. This is the single most common reason for poor performance. Ideally, the water should be aerated and the nutrient bath temperature should not exceed 80 F, with 74-76 F being optimum.


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Bucket Systems (Including the CAP Ebb and Grow)

Will using STG in my bucket system change the amount of water required to flood my system?

We have examined multiple theoretical approaches to this question and have tested the application as well and found that there is no net difference between the amount of water necessary to flood the system, regardless of media used.

Do I have to pre-treat my insert before installing it into my hydroponic system?

No, STG is ready out of the box and requires no pretreatment.

Will I have to stake or trellis my plants if I use STG?

Most plants will not requiring staking or trellising unless the total overall height exceeds four feet. This is only a rough guideline and common sense should be applied whenever a new variety is grown.


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Aeroponic Systems (Including the Aeroflo (GH) series and most cloner systems)

What size insert will I need for my Aeroflo system?

Our 3” Arroyo insert was designed specifically for use in the Aeroflo system. However, it also performs exceptionally in any hydroponic system that employs 3” net pots.


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Flood and Drain

Should the container in which the plants reside allow for standing water at the end of a flood cycle (i.e. C.A.P Ebb and Grow)?

No. Standing water is an opportunity for anaerobic bacteria to multiply in the root zone of the plant. Encourage all growers to retrofit their systems to drain completely. Be certain to preface this recommendation with the statement “regardless of media, this modification is beneficial”. We do not, under any circumstances, want to infer that our product is somehow broken or needs modification to work properly.

Is a 15 minute flood cycle optimum for STG?

No. Optimally, a five minute flood would be used. Unfortunately, most analog timer manufacturers only produce timers with 15 minute increments.

How can I use STG in my traditional flood and drain system?

STG has produced a wide range of products that work seamlessly in traditional flood and drain applications. Any of our Storm Series inserts, when placed in an appropriate size net pot or cup will work exceptionally well in a standard flood and drain application, while our core line of products was initially designed for this application. Within the core line, there are many products that will be familiar to any hydroponic grower: cubesblocksslabs and flood table mats. When mated together, these products provide unmatched ease of use and uncompromising performance. It is, however, important to understand that STG does not wick or rely on capillarity to feed plants. This is critical in a flood table. The flood height must coincide with the root placement of your cutting or starts. If the level is too low, it will not reach the roots and the plants will become stressed. The benefit of this design becomes evident almost immediately as the grower is able to feed more often and flush the system easily without excessive amounts of water commonly associated with other hydroponic media options.

How often do I flood my system when using STG?

The standard 4 X 15 min model works with STG but we have found performance increases with an increase in interval and a decrease in duration. For example, 4 x 15 could be replaced by 12 x 5 and still maintain the same total time value while increasing overall performance and yield.


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Super Modified Raft Systems

How do I build a Super Modified Raft (SMR) system?

The super modified raft used in our videos is a simple retrofit design of a common flood table. First, it is important to identify that this system cycles continuously, so a timer is not necessary. Second, set your drain riser to whatever height you prefer the water to fill to. Our water level is set just below the lip of the table at about 3.75”.

Next, you must accurately determine how much aeration is necessary for optimum performance. This is done by first calculating the amount of “working water” in the table. This can be accomplished through a series of simple calculations.

  • Obtain the inside length value and multiply it by the inside width value.
  • Take that total and multiply it by the height of the water you set with your drain riser to in the prior step.
  • Convert these values to inches and multiply by .00433 to arrive at gallons.
  • Once you have gallons, multiply that value by 25.

The value obtained from the last equation is an estimate of the amount of air you would like to displace in this system for optimum performance. To determine how much air a pump displaces, look at the box or spec sheet. Once you have this value, add enough pumps and stones to accomplish your target aeration value.

You will also need a sheet of 1.5”-1.75” thick construction foam which will be used for the raft and should be readily available at your local big box hardware retailer. It is commonly sold in 4’ x 8’ sheets and generally located near the lumber. Once you have obtained the foam, cut it to fit the inside dimensions of your table. You must ensure the dimensions of the raft are slightly smaller than the actual dimension or the raft will not rise and fall with the water volume.

Now determine the site spacing and net pot size you would like to use. For those of you who grow using a S.O.G model, spacing 3”-4” net cups every 8” on center seems to work pretty well. If your goal is to grow large specimen plants in excess of 3’ our 6” x 4.75” insert would likely work best using a 16” on center spacing. These are merely guidelines and should be regarded as such.


Can I grow large plants in a SMR system?

Absolutely. In fact, I find growing large plants easier in a SMR system than in nearly any other design currently employed.


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Top Water (including Slabs)

Can I use STG products if I currently use a top drip system?

Yes, STG can be used in top drip applications. However, optimum results have not been realized when using a “waterfarm” or similar design. Standard dripper stake systems as well as slab systems have performed well and we manufacture a wide variety of products designed specifically for the aforementioned applications.

How often should I water in a top drip system if I am using STG?

When running a slab system, I have had good results running irrigation continuously with an inline 1.5- gph pressure compensating emitter.


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STG Comparison to Other Plant Growth Substrates
Product AttributeSTGRockwoolOasisCoirHydrotonPerliteSoilless MixSoil Conditioner
Weight – lb. / cubic ft.
Presoaking required?NoYesYesYesYesYesNoNo
pH neutral?YesNoYesNoYesYesVariesNo
Nutrient build-up on surfaceNoYesYesNoYesYesYesNo
Starter nutrientsNoYesYesYesNoNoYesNo
Cation Exchange Capability (CEC)0.00.0Low60-130/megHigh0.0VariesVaries
Lung/skin irritationNoYesNoNoNoYesNoNo
Shelf lifeIndefiniteFiniteFiniteFiniteIndefiniteIndefiniteFiniteFinite
Labor intensive – setupLowLowLowHighHighHighHighHigh
Labor-intensive – post harvestLowMediumLowHighHighHighHighMedium
Storage space requiredLowHighMediumHighHighHighHighHigh