AutoPot FlexiTanks Collapsible Water Reservoirs | Happy Hydro
A full reservoir that folds into a box
AutoPot FlexiTanks are collapsible water reservoirs that ship flat and assemble in minutes with no tools. They fold down for storage between grows and fit in spaces where rigid tanks cannot. Available from 6.6 gallons up to 105 gallons (PRO), each FlexiTank includes a built-in tap and connects directly to your AutoPot system with 3/8" fittings.
Free shipping on orders over $49
30-day returns on all orders
Serving growers since 2006
Compare
Rigid reservoir vs. FlexiTank
Rigid Reservoir
Takes up permanent floor space even when empty
Hard to clean corners and seams where algae and mineral deposits build up
No internal capacity markings on most models
FlexiTank
Folds down and stores away when not in use
Smooth interior with no corners, easy to rinse and dry between grows
PRO models include internal capacity markings and reflective skin
Gallery
FlexiTank setup and assembly
Features
What makes the FlexiTank practical
Fully Collapsible Folds flat
Every FlexiTank folds into a single box for storage or shipping. The 25-gallon model ships in a box just 31" x 7" x 5" and weighs 4.4 lbs.
No Tools Required
Assembly means unfolding the tank, inserting the support frame (25g and up), and filling with water. The whole process takes a few minutes.
Built-in Tap
Every FlexiTank includes a tap fitting that connects to 3/8" OD tubing. FlexiTanks purchased with a system bundle include a click-fit tank filter.
PRO Models: Reflective and Light-Tight
The PRO line adds a reflective outer skin that blocks light, internal capacity markings, and concealed reservoir supports for a cleaner look.
Elevate for Gravity Pressure
Raise the FlexiTank at least 6 inches above the highest AQUAvalve for proper flow. Install your inline filter away from the tap to avoid pulling on the tank wall.
Standard vs. PRO
Standard FlexiTanks come in 6.6, 13, and 25 gallon sizes. PRO models (25 and 105 gallon) add the reflective skin, capacity markings, and hidden supports.
Specs
FlexiTank dimensions by size
6.6 Gallon
11.8" dia x 14.6" H, 2.9 lbs
13 Gallon
13.8" dia x 20.9" H, 4 lbs
25 Gallon
17" dia x 29.5" H, 4.4 lbs
25G PRO
19" dia x 27.5" H, 8.4 lbs
105G PRO
28.9" dia x 41.3" H
Assembly
No tools, minutes
Tap Fitting
3/8" OD connection
Min. Elevation
6" above AQUAvalve
How to set up your FlexiTank
1
Unfold and position
Remove the FlexiTank from the box and unfold it where you want it to sit. For 25 gallon and larger models, insert the internal support frame before filling.
2
Elevate the tank
Place the FlexiTank on a stand or platform at least 6 inches above the highest AQUAvalve in your system. This provides the gravity pressure needed for proper flow.
3
Connect fittings
Attach your inline filter to the tubing (not directly to the tap) and run 3/8" OD tubing from the tank tap to your inline tap and then to your first AQUAvalve tray.
4
Fill and run
Fill the tank with water and nutrients. Open the tap and let the system start. When the season ends, drain, fold, and store the FlexiTank until next time.
Which size do I need? A good rule: each 3.9g pot uses roughly 1 to 2 gallons per week at peak growth. A 4-pot system does well with a 25-gallon tank, giving you roughly 1 to 2 weeks between refills. Call or email us: 716-217-0353 / help@happyhydro.com
See also: The 12.4 Gallon Hard Tank is a rigid alternative for smaller setups. Use Easy2Flow to clean your FlexiTank between grows.
Questions
Frequently asked questions
FlexiTanks are built from thick, flexible material with sealed seams. Leaks are rare and almost always caused by punctures from sharp objects underneath the tank. Place it on a smooth, flat surface and you should have no issues. Many growers use the same FlexiTank for years.
Standard FlexiTanks are the original design: collapsible, durable, and functional. PRO models add a reflective, light-tight outer skin that blocks algae growth, internal capacity markings so you can see your water level, and concealed support frames for a tidier appearance. Both use the same fittings and accessories.
The tank needs to be elevated at least 6 inches above the highest AQUAvalve in your system. Any sturdy, level surface works. If your trays are on the floor, even a short table or cinder blocks will do. We also sell the AutoPot 12.4g tank stand, which works well for smaller FlexiTanks.
Yes. The FlexiTank is just a water reservoir with a tap. You can use it for any gravity-fed setup or as a general-purpose water storage container. The tap accepts standard 3/8" OD tubing.
Drain the tank, rinse the interior with clean water, and use Easy2Flow reservoir cleaner to remove any mineral buildup or biofilm. Let it air dry before folding for storage. Cleaning between cycles is important for preventing contamination in your next run.
If you receive a defective or damaged unit, email us a photo at help@happyhydro.com and we'll make it right immediately: replacement or refund, your call. For change-of-mind returns, we accept returns within 30 days for items in new, resalable condition. If you're not sure whether this product is right for your setup, call us first at 716-217-0353. We'd rather answer your questions before you order.
Happy Hydro has been selling growing equipment since 2006. We've carried AutoPot for years because the systems work great and customers who buy them leave happy. Have questions before you order? Call 716-217-0353 or email help@happyhydro.com. We're easy to reach and happy to help!
Questions? We're easy to reach. Happy Hydro has been serving growers since 2006. Call or email us before you order, after you order, or any time something comes up. When you're happy, we're happy.
We ship fast from Buffalo, NY. Most orders land at your door in 3-5 business days. Free standard shipping on orders $49+, plain-box packaging, and real humans ready to help if anything goes sideways.
Free shipping on orders over $49
Plain-box discreet packaging
Serving growers since 2006
What to expect
When you order from Happy Hydro
Fast & Free on Orders $49+
Free standard shipping to the lower 48. Most orders ship same or next business day from our Buffalo, NY warehouse via UPS Ground or USPS Ground Advantage. Expedited options available at checkout. * Soils may incur added fees for Western US delivery * Some products ship direct from the vendor's warehouse to keep prices lower and get your order there faster
Every order ships in a plain brown box with no branding or logos. Your purchase stays 100% private. We can also ship to your local UPS Store on request.
Specs
Shipping details at a glance
Delivery time
3-5 business days
Default carrier
UPS Ground or USPS
Signature required
Orders over $500 only
Free shipping threshold
$49+ to the lower 48
International
Canada only Email help@happyhydro.com your address & a screenshot of your cart for a quote
Returns
30 days on most orders Exceptions apply — orders over $400, multi-box shipments, and some vendor items may incur return shipping charges. Full policy
Questions
Frequently asked questions
Shipping
Check the order confirmation sent to your email or phone after checkout — it includes a tracking link. If you use the Shop App, you can track your order there too.
Most orders arrive in 3-5 business days. Expedited options (2-day, overnight) are available at checkout if you need it sooner.
Signature is only required on orders over $500. For added privacy, we can ship to your local UPS Store so you pick it up on your own schedule — just ask.
We default to UPS Ground or USPS Ground Advantage. Select an expedited option at checkout and we'll use the appropriate carrier for that service.
P.O. boxes: Yes, for small and lightweight items.
International: Canada only. Email help@happyhydro.com your address and a screenshot of your cart for a shipping quote.
APO/FPO: Not currently available.
For Canadian orders, import duties and taxes are the buyer's responsibility. You'll complete payment using your tracking number at UPS.com when your package arrives.
Title and risk of loss pass to you once we hand off to the carrier, but that doesn't mean we leave you hanging. Email help@happyhydro.com and we'll work overtime to track it down and make it right.
Payment
We accept credit/debit cards, PayPal, Coinbase, and Happy Hydro gift cards. Your card is charged immediately at checkout.
Double-check your billing address and card number. For larger purchases, your bank may have flagged it — a quick call to authorize the transaction usually sorts it out.
Promotions
Enter your code in the "Promo code" box at checkout and click Apply. One code per order, but you can combine a gift card with a promo code if you have both.
Subscribe to our mailing list for exclusive discounts and early access to sales. You can sign up at the bottom of any page on our site.
Returns & Cancellations
Email help@happyhydro.com within 30 days of delivery and we'll get you a refund or replacement, your choice. Items must be in original packaging with all parts in resalable condition. Multi-light orders, grow tents, orders over $500, and multi-box shipments may incur return shipping charges. AK, HI, and international buyers are responsible for return and warranty shipping. Some vendor-specific policies may apply — check the product page for details.
Refunds are processed through Shopify within 10 business days. Most customers see the credit back in about 5 days.
Reply to your order confirmation email or email help@happyhydro.com as soon as possible. Canceled orders may incur a processing fee depending on your payment method:
Credit/debit card: 2.9%
PayPal or Venmo: 3.5%
International PayPal: 4.0%
American Express: 4.1%
Shop Pay Installments / PayTomorrow: 6.5%
Support & Policies
Call or chat with our grower support team at 716-217-0353, Monday-Friday 10 am-4 pm EST. You can also email help@happyhydro.com any time and we'll get back to you quickly.
Happy Hydro began as a pipe dream in a garage and has grown into something built almost entirely on word of mouth and repeat customers. Rather than focusing on raising margins and obsessing over profits, we've always believed that the right combination of competitive prices, superior products, and world-class customer service speaks for itself. Our philosophy will never change: when you're happy, we're happy.
Our commitment
What you can expect from Happy Hydro
Real People, Real Growers
Our grower support team isn't a call center. They know the products because they're passionate about growing. Reach us Monday-Friday, 10 am-4 pm EST at 716-217-0353 or help@happyhydro.com, before you order or after.
Hand-Picked by Growers, for Growers
Every brand we carry was chosen by our founders because it performs. We only stock premium brands we believe in, and every item is inspected before it leaves our warehouse.
Fair Prices and Free Shipping
We work hard to keep our prices as low as manufacturers allow, and we include free shipping on orders over $49 so there are no surprises at checkout. Find a lower price anywhere and we'll match it.
Authorized for Every Brand We Carry
We're an authorized dealer for every manufacturer on our site. That means you get the full manufacturer's warranty on every purchase. No grey market, no expired stock.
30-Day Returns on Most Orders
Hard to commit to a product you haven't tried. Return most items within 30 days in original condition and we'll take care of it. Read the full policy.
Secure Shopping, Private Data
Every transaction is SSL encrypted. We don't store payment information and we will never sell your data to anyone, ever.
Volume and Commercial Pricing
If you're a commercial grower or putting together a large order, reach out before you buy. We have pricing available that we can't advertise publicly. Call 716-217-0353 or email help@happyhydro.com and we'll take care of you.
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Payment & Security
Your payment information is processed securely. We do not store credit card details nor have access to your credit card information.
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