Budget Build: Set Up a 20‑Gallon Community Tank Under $200
1) The $200 Plan: What to Buy (and What to Skip)
The constraint: Build a reliable, quiet, attractive 20‑gallon freshwater community for ≤ $200 (before fish). Prices vary by region, but with careful picks you can hit the target without buying junk. The key is prioritizing filtration, heater, and light—the parts that keep fish alive and plants growing. Décor can be DIY. Fancy controllers and premium stands can wait.
Shopping list that punches above its price:
- 20‑gallon glass tank (20‑long if possible for swimming space).
- Sturdy DIY stand or flat furniture you already own that meets weight and leveling requirements (see Placement 101). If buying new, a basic metal rack often beats particleboard.
- Filtration: large sponge filter + air pump or a value HOB rated for 30–40 gallons. Add extra coarse sponge as a pre‑filter and a bag of ceramic rings for biological capacity.
- 100W adjustable heater with thermostat and indicator light.
- Light: budget LED strip with a true daylight spectrum (6–8 hours/day is sufficient for low‑light plants).
- Substrate: 20 lb bag of inert sand or fine gravel.
- Water conditioner (dechlorinator) and a basic liquid test kit.
- Hardscape: locally collected rocks/wood (safety‑checked) or inexpensive landscaping stone; zip ties and superglue gel for assembly.
- Plants: hardy, low‑light starters—Anubias, Java fern, Vallisneria, Amazon sword, hornwort, or floating Salvinia.
What to skip (for now): canister filters, CO₂ systems, expensive branded “starter kits” with weak lights, bottled “cures” for every algae, and most decorations that don’t provide function. Every dollar should aim at biology, stability, and ease of maintenance.
2) Assembly: Fast, Clean, and Safe
Dry fit first. Place the tank on the leveled stand, route cables with drip loops, and position the power strip high inside the stand. Rinse substrate until the water runs mostly clear, then add 1.5–2 inches (4–5 cm). Build your hardscape: wedge rocks securely, zip‑tie wood if needed, and test that nothing tips when nudged.
Fill without dust storms. Put a plastic bag or plate on the substrate and pour dechlorinated water onto it to avoid craters. Install the heater and filter, and add an air stone for extra oxygen. Seed the filter if you can (sponge from a friend’s tank), then start a fishless cycle using bottled ammonium chloride or a tiny pinch of food (see Cycling Overview).
Lighting and plants. Plant easy species right away: anchor rhizomes to wood/rock (don’t bury), tuck root tabs under heavy root feeders if you have them, and run the light 6–7 hours. Floaters help balance nutrients while the tank matures.
Noise control. Pad the air pump with foam, ensure the HOB sits level and primed, and place rubber feet under the stand. Tighten screws after the first week as wood settles.
3) Stocking on a Budget: Fish, Plants, and Hardscape
Fish that fit the budget and the tank:
- Schoolers: 12 ember tetras or 10 harlequin rasboras.
- Bottom crew: 6 pygmy corydoras or 6 kuhlis (with sand).
- Centerpiece: 1 honey gourami (peaceful, colorful, inexpensive).
Plants that thrive under a budget LED: Anubias and Java fern for texture, Vallisneria for a fast vertical background, and a sword or crypt for midground structure. A few floating stems (hornwort, water sprite) accelerate balance. You don’t need CO₂—consistent water changes and a modest fertilizer keep things green.
DIY hardscape & background. Landscaping slate, river stones, and found branches (de‑barked, boiled, and soaked) make beautiful layouts. A black vinyl or painted back panel hides cables and makes fish pop.
Staged spending. If $200 is tight, prioritize: tank + sponge filter + heater + light + sand + conditioner + test kit. Add a HOB later if you want more polishing power; add more plants with your first livestock purchase.
4) Running Costs: Electricity, Food, and Water
Electricity. A 100W heater cycles on/off; in a heated home it might average 25–40W. A sponge/HOB uses ~3–7W, and a budget LED strip ~15–20W during its 6–8 hour photoperiod. Expect a few dollars per month in most regions—less than streaming subscriptions.
Food & consumables. One small container of quality pellets and a pack of frozen baby brine shrimp cover a month or two for a 20‑gallon. Water conditioner lasts many months at typical dosages. Replace floss monthly and rinse sponges forever.
Water. Even with weekly 30% changes (6 gallons), the cost is negligible in most cities. If you use RO/DI, factor in filters and waste water; most budget builds do fine on conditioned tap.
Hidden costs to avoid. Don’t buy fish twice—quarantine new additions. Don’t chase every algae with a new chemical—adjust light and nutrients. Don’t oversize equipment that hums and heats the room—choose efficient, reliable basics.
FAQ
Is a canister necessary for a 20‑gallon?
No. A large sponge or a decent HOB with added biological media is quiet, cheap, and very effective for this size.
Can I keep shrimp in a budget build?
Yes—neocaridina do well with stable parameters and a sponge pre‑filter to protect babies. Provide moss and lots of biofilm.
What if my tap water is very hard?
Use inert sand/gravel and choose hard‑water‑tolerant fish (livebearers, rainbows). Soil and RO/DI can wait for advanced builds.
Next reads: Filter Sizing by Tank Volume • Heater Sizing & Placement • Low‑Tech Planted Tanks