Algae in the reservoir: causes and prevention
Algae grows wherever light hits nutrient solution. It swings your pH, depletes overnight oxygen, and clogs drip lines. Light exclusion solves 90% of it.
Soilless growing for food crops. EC, nutrients, lighting, the works.
Hydroponic systems work on a single principle: roots get water + nutrients + oxygen, and you control all three. Compared to soil growing, you trade compost and intuition for measurement and dosing. The tools here help with the measurement part.
Crop choice constrains everything else. Lettuce wants EC 1.0-1.4 and 22°C; tomatoes want EC 2.5-3.0 and 24°C. They don't share a reservoir well. The edible plant catalog has 231 crops with growing-system compatibility, EC ranges, light needs, and notable cultivar guidance for many species. Filter by your climate zone if you're growing outdoors or in a greenhouse.
The garden planner asks for your roster and growing system (DWC, NFT, vertical tower, drip, media bed, wicking, soil bed) and tells you whether the combination works. The 13 compatibility rules catch the classic mistakes: tomatoes in NFT channels won't work, lettuce and tomatoes can't share a reservoir at the same EC, deep-rooted crops in vertical towers will clog.
Once your roster is validated, the planner produces a target EC, target pH, NPK ratio, and per-crop deltas showing the tradeoff. Two approaches available: a balanced overlap target (default) or a dominant-feeder target (commercial mixed-bed standard). Per-crop growth stage matters; the planner lets you set each crop's stage independently for honest mixed-stage math.
The nutrient mix calculator gives you exact grams of Masterblend, GH Flora, or generic NPK blend per liter of reservoir at your target EC. The EC ↔ PPM converter handles the 500/640/700 PPM scale confusion that cheap TDS meters create.
Indoor and greenhouse hydroponics live or die on the grow light calculator check. Each crop has a DLI target; the calc tells you whether your fixture × hours × PPFD achieves it. Lettuce at DLI 12 is fine; tomatoes need DLI 25+ to fruit. Mismatched lighting is the most common reason indoor hydroponic systems underperform.
Vapor pressure deficit is the temperature-and-humidity sweet spot that maximizes transpiration without stressing plants. Hobby growers can skip this; serious indoor growers can't.
The running cost calculator gives you a monthly electricity estimate for the pump, lights, and any heating/cooling. Indoor hydroponics under lights costs $50-200/month at typical electricity rates; greenhouse setups are far cheaper. Worth knowing before you scale up.
Algae grows wherever light hits nutrient solution. It swings your pH, depletes overnight oxygen, and clogs drip lines. Light exclusion solves 90% of it.
A peristaltic pump, an EC sensor, and a controller can keep your reservoir at target concentration automatically. What it costs and whether it's worth it.
Cal-mag issues cause more hydro problems than NPK ever will. When your tap water provides enough, when it doesn't, and what deficiency looks like.
Pathogen carryover between crops is the silent yield killer. How to sanitize reservoirs, channels, and tubing with bleach, peroxide, or isopropyl alcohol.
Take a cutting, root it, and transplant into your system. The technique works for basil, tomatoes, peppers, mint, and most herbs. 7-14 days to roots.
Daily Light Integral measures total photons delivered per day. It's how plants experience light, and it's why a dim light running 18 hours can outperform a bright light running 8.
Kratky is passive and free to run. DWC adds an air pump for oxygenation. The difference matters most for large plants and fruiting crops.
Lighting is 70-85% of your power bill. A countertop herb setup runs about $8/month. A serious grow tent costs $30-80/month. The math by system size.
The inverse square law means doubling the distance quarters the intensity. How to find the right height for your light and what PPFD maps actually show you.
Basil, mint, cilantro, and chives grow 25-40% faster hydroponically than in soil. Actual yield comparisons and the lowest-effort systems that work.
The research mostly says yes. Mineral content depends on what you feed the plant, not where its roots are. What the studies actually measured and what they missed.
Peppers love hydro's consistent feeding and warm root zones. EC targets by growth stage, which varieties stay compact enough for indoor growing, and pollination tips.
Strawberries in hydro need chilling hours, hand pollination, and runner management. Which varieties work indoors and what the realistic yield looks like.
Indoor hydro tomatoes need pollination, pruning, EC management by growth stage, and serious light. How to grow them from seed to ripe fruit.
Seed to harvest in 7-14 days, no nutrient solution needed, and high margins if you sell them. Seed density, growing media, and the basics of production.
Dry salts cost a fraction of premixed liquid nutrients and last for years on a shelf. The mixing order matters, and getting it wrong locks out calcium.
NFT systems need the right slope (1:30 to 1:40), flow rate (1-2 L/min), and channel length (under 12 m). The math that keeps roots wet without drowning them.
Mobile nutrients show problems on old leaves first. Immobile nutrients hit new growth. Here's how to tell nitrogen, iron, calcium, potassium, and magnesium apart.
Fungus gnats, aphids, spider mites, and thrips are the four pests you'll actually encounter indoors. How to identify, prevent, and treat each without pesticides.
pH drift in hydroponic reservoirs is caused by nutrient uptake, not bad water. Plants release ions as they feed, and the direction of the drift tells you what they're consuming.
Pythium thrives in warm, low-oxygen nutrient solution. Keep reservoir temperature under 22 C, maintain 8+ ppm dissolved oxygen, and here's what to do if you're already infected.
Rockwool, rapid rooters, and peat plugs each have trade-offs. How to germinate seeds for hydro transplant with reliable germination rates by crop.
Warm nutrient solution holds less oxygen and breeds more pathogens. Chilling methods ranked by cost, effectiveness, and system size.
A PVC tower with net cups and a small pump grows 20-30 plants in under half a square meter. Materials, sizing, and which crops actually work vertically.
Hard water, soft water, well water, city water. What's in your tap affects everything you add after. When to filter and when to work with what you've got.
Ranked by forgiveness, not by what's possible. Lettuce first, tomatoes last, and the reasons for the order.
EC measures conductivity. parts per million is derived with three different conversion factors, which is why your meter and your nutrient bottle disagree.
Kratky, DWC, drip, and NFT compared for cost, complexity, and crop range. What to build if you've never grown without soil.
The simplest hydroponic method. A jar, nutrient solution, and a seedling. No pump, no timer, no power. What it can and can't grow.
PAR, PPFD, DLI decoded. How to measure light at canopy level, which crops need how much, and how to size a light without overspending.
What's in a hydroponic nutrient solution, what N-P-K ratios mean at each growth stage, and how to read deficiency symptoms.
What vapor pressure deficit is, why it predicts plant stress better than relative humidity alone, and how to keep it in the right range.