The TankMind Blog
Specific, practical aquarium guidance, not generic advice. Reef and freshwater, written for hobbyists who want the actual answer.
How to Cure Fin Rot in Bettas and Other Fish
Fin rot is a bacterial or fungal infection triggered by poor water quality. Here is exactly how to identify it, treat it, and help fins grow back.
August 14, 2026MaintenanceNitrite High but Ammonia Low: Causes and Fixes
High nitrite with low ammonia is the normal second stage of the nitrogen cycle. Here is what causes it, how long it lasts, and how to keep your fish safe.
August 13, 2026BeginnerHow Many Fish Fit in a 10 Gallon Tank
The honest answer depends on species, filtration, and tank shape, not a simple number. Here is what actually determines your 10 gallon stocking limit.
August 12, 2026MaintenanceBetta at Tank Bottom Not Eating: Causes and Fixes
A betta sitting at the bottom and refusing food is signaling a problem. Here are the verified causes and what to do first.
August 11, 2026MaintenanceHow to Lower Ammonia in a Fish Tank Fast
Ammonia spike? Start with a partial water change right now. Here is everything a worried keeper needs to know, step by step.
August 10, 2026DiseaseWhy Your Corals Won't Open or Are Dying
Corals close and die for specific, fixable reasons. Learn the most common causes, how to tell which one you have, and what to do about each.
August 9, 2026BeginnerAquarium Water Changes: How Often and How Much
Change 25 to 30% of your aquarium water weekly. Here is exactly why, how to adjust for your tank, and what to avoid.
August 8, 2026MaintenanceHow to Lower Nitrates Without Big Water Changes
Nitrates creeping up? You can control them with plants, refugiums, feeding habits, and filter media, no massive water changes required.
August 7, 2026DiseaseWhy New Fish Keep Dying and How to Stop It
New fish usually die from one of six fixable problems. Here is how to identify which one is hitting your tank and what to do right now.
August 6, 2026DiseaseHow to Treat Ich (White Spots) and Stop It Fast
White spots on your fish mean ich. Here is exactly how to treat freshwater and marine ich, step by step, based on the parasite's life cycle.
August 5, 2026BeginnerHow Long to Cycle a Fish Tank (and Know It's Done)
Most tanks take 4 to 8 weeks to cycle. Here is exactly what drives that timeline, how to confirm it is finished, and what to do if it stalls.
August 4, 2026FreshwaterBetta Fish Care Guide: Setup, Feeding, and Tank Mates
Everything a beginner needs to know about keeping Betta splendens healthy, from tank size and water temps to feeding and compatibility.
August 3, 2026MarineBanggai Cardinalfish Care Guide for Saltwater Tanks
Everything beginners need to know about keeping Banggai Cardinalfish, from tank setup and water parameters to diet, temperament, and common mistakes.
August 2, 2026MarineGreen Chromis Care Guide for Saltwater Tanks
Learn how to keep Green Chromis thriving with the right tank setup, water parameters, diet, and compatible tank mates for a peaceful reef.
August 1, 2026MarineYellow Watchman Goby: Complete Care Guide
Everything beginner saltwater aquarists need to know about keeping the Yellow Watchman Goby, from tank setup to feeding and tank mates.
July 31, 2026MarinePurple Firefish Care Guide for Saltwater Tanks
Everything beginners need to know about keeping the Purple Firefish, from tank setup and water parameters to diet, tank mates, and common mistakes.
July 30, 2026MarineFirefish Goby Care Guide for Saltwater Beginners
Everything beginner saltwater aquarists need to know about keeping the Firefish Goby, from tank setup and water parameters to feeding and compatible tank mates.
July 29, 2026MarineRoyal Gramma Care Guide: Is It Right for You?
Everything a beginner saltwater aquarist needs to know about keeping the Royal Gramma, from tank setup to feeding and compatible tank mates.
July 28, 2026MarinePercula Clownfish Care Guide for Saltwater Beginners
Learn exactly how to keep the Percula Clownfish healthy, from water parameters to feeding, tank mates, and common beginner mistakes.
July 27, 2026MarineOcellaris Clownfish Care Guide for Beginners
Everything a beginner needs to know about keeping the Ocellaris Clownfish, from tank size to feeding, temperament, and compatible tank mates.
July 25, 2026MaintenanceCloudy Aquarium Water: Why It Happens and How to Fix It
Cloudy aquarium water is usually caused by a bacterial bloom, algae bloom, or substrate dust. Here is how to tell which you have and what to do.
July 24, 2026MarineAiptasia Removal: Comparing the Methods That Actually Work
Aiptasia removal works best with chemical injection, peppermint shrimp, or Berghia nudibranchs.
June 8, 2026FreshwaterWhy Shrimp Die From Products That Don't Bother Fish
Shrimp die from fish-safe products because they use copper-based hemocyanin, not hemoglobin. Learn which products are dangerous and how to protect your colony.
May 25, 2026DiseaseRTN and STN: What to Do in the First Hour
RTN and STN can kill a coral in hours. Act in the first 60 minutes by fragging below the necrosis line, isolating the frag, and checking parameters immediately.
May 11, 2026FreshwaterDiscus Water Quality: Why They're Considered Difficult (And What That Actually Means)
Discus water quality is demanding because these fish need precise, stable conditions with very little room for drift. Learn what that actually means for your tank.
May 4, 2026FreshwaterManaging Aggression in African Cichlid Tanks
Managing aggression in African cichlid tanks starts with understanding that some chasing is normal. Learn which strategies actually reduce harmful aggression.
April 27, 2026MaintenanceReef Tank Vacation Checklist: What to Actually Prepare
Get your reef tank vacation checklist right before you leave: auto top-off, automatic feeder, a check-in person, and remote monitoring are the four essentials.
April 20, 2026EquipmentApex vs. GHL: Which Aquarium Controller Should You Buy?
Apex vs. GHL: both are excellent aquarium controllers, but the right choice depends on your community, setup complexity, and how you prefer to configure automation.
April 13, 2026FreshwaterMystery Snails vs. Nerite Snails: Which Cleanup Crew Member Do You Need?
Mystery snails and nerite snails serve different roles. Nerites tackle tough algae without breeding in freshwater; mystery snails are larger, more active
April 6, 2026FreshwaterCorydoras Care: Why School Size Matters More Than Most People Think
Corydoras need a school of at least 6 to thrive. Learn why group size matters so much for cory health, behavior, and how to stock them correctly.
March 30, 2026EquipmentWhy an Auto Top-Off System Is the Best $50 You'll Spend
An auto top-off system keeps salinity stable by replacing evaporated water automatically. Here is why it is the best low-cost upgrade for any reef tank.
March 23, 2026MarineCan Phosphate Be Too Low? Yes, And It Can Bleach Your Coral
Phosphate can absolutely be too low in a reef tank. When phosphate drops to near 0 ppm, corals can bleach just like they do during a heat event.
March 16, 2026BeginnerBrown Algae (Diatoms) in a New Tank: Why It Happens and When It Stops
Brown algae (diatoms) in a new tank is normal and resolves within 2 to 8 weeks as silica depletes and competing organisms establish. Here is what to expect.
March 9, 2026FreshwaterBettas Don't Belong in Bowls: What Tank Size They Actually Need
Bettas need at least 5 gallons, not a bowl. Learn what tank size, filtration, and heating bettas actually require to live 3 to 5 years.
March 2, 2026MarineWhen Do You Actually Need to Dose Magnesium?
Dose magnesium when levels fall outside 1250 to 1350 ppm or when calcium and alkalinity refuse to stabilize despite correct dosing. Here is how to know and what to do.
February 23, 2026EquipmentLive Rock vs. Dry Rock: Which Should You Start With?
Live rock cycles faster and adds biodiversity, but carries pest risk. Dry rock is safer and cheaper but starts inert. Here is how to choose.
February 18, 2026BeginnerTank-Bred vs. Wild-Caught: Does It Actually Matter for Your Tank?
Tank-bred fish are almost always hardier and easier to keep than wild-caught. Here is what that means for your tank and when wild-caught is still the right call.
February 16, 2026FreshwaterLive Plants vs. Plastic Decorations: The Real Tradeoffs
Live plants improve water quality and outcompete algae, but plastic decorations have real advantages too. Here are the honest tradeoffs for freshwater tanks.
February 9, 2026MarinePAR Explained: How Much Light Does Your Coral Actually Need?
PAR measures usable light reaching your coral, not just power draw. Learn target ranges for soft corals, LPS, and SPS, and how to acclimate safely.
February 4, 2026FreshwaterSponge Filters vs. HOB Filters: Which Is Right for Your Freshwater Tank?
Sponge filters protect fry and shrimp with gentle flow, while HOB filters offer more capacity for community tanks. Here is how to choose between them.
February 2, 2026FreshwaterSubstrate Choice: Planted Soil, Sand, or Bare Bottom?
Planted soil, sand, or bare bottom: your substrate choice shapes plant health, fish behavior, and water chemistry. Here is how to pick the right one.
January 28, 2026EquipmentHeater Failure: The Most Preventable Tank-Killing Event
Heater failure can cook your tank within hours if a heater sticks on. Learn the exact precautions and steps that prevent this from killing your fish.
January 21, 2026Beginner5 Salt Mixing Mistakes That Wreck New Saltwater Tanks
Avoid these 5 salt mixing mistakes that wreck new saltwater tanks: bad timing, uncalibrated tools, in-tank mixing, poor water quality, and inconsistent ratios.
January 19, 2026MaintenanceCloudy White Water: Bacterial Bloom Explained
Cloudy white aquarium water is almost always a bacterial bloom. Learn what triggers it, how to tell it apart from green or brown cloudiness, and what to do.
January 12, 2026MarinePairing Clownfish With an Anemone: What Actually Works
Pairing clownfish with an anemone works best when the anemone is healthy first and species are matched, but hosting is never guaranteed even with the right combo.
January 5, 2026BeginnerThe Drip Acclimation Method, Step by Step
Drip acclimation gradually matches shipping water chemistry to your tank over 30 to 60 minutes, protecting fish from pH and salinity shock beyond temperature alone.
December 24, 2025MaintenanceHow Often Should You Actually Change Water? It Depends on Your Tank Type
How often you should change water depends on your tank type, stocking level, and nutrient trends, not a single rule. Here is how to find your real schedule.
December 10, 2025MarineWhy Coralline Algae Isn't Spreading in Your Reef Tank
Coralline algae stops spreading when calcium, alkalinity, or magnesium are unstable. Learn the exact blockers and how to fix them for a thriving reef tank.
November 26, 2025Beginner8 Saltwater Fish That Actually Survive Beginner Mistakes
These 8 saltwater fish survive beginner mistakes because they tolerate parameter swings, imperfect cycling, and inconsistent feeding better than most species.
November 12, 2025FreshwaterGH and KH Explained: Why Your Freshwater Plants and Fish Care
GH measures calcium and magnesium while KH measures pH buffering capacity. Learn why both parameters matter for freshwater fish, plants, and invertebrates.
October 29, 2025DiseaseFin Rot: Causes, Treatment, and When It's Actually Something Else
Fin rot is a bacterial infection triggered by poor water quality or stress, not a standalone disease. Learn the real causes, treatments, and how to prevent it.
October 15, 2025FreshwaterDIY CO2 vs. Pressurized CO2 for Planted Tanks: Which Should You Buy?
DIY CO2 costs just a few dollars to start but delivers inconsistent output. Pressurized CO2 runs $150 to 300 and is the only reliable path to high-tech planted tanks.
October 1, 2025MarineThe Calcium, Magnesium, and Alkalinity Triangle Explained
Calcium, magnesium, and alkalinity work as a linked system in reef tanks. Learn the target ranges, why they interact, and how to keep all three stable.
September 16, 2025EquipmentWhy Your Protein Skimmer Isn't Producing Skimmate
A protein skimmer that runs but collects no skimmate usually has a water level, airflow, or organic load problem. Here is how to diagnose and fix it.
September 2, 2025Beginner5 Signs You're Overfeeding Your Tank (And What to Do About It)
Overfeeding your tank causes cloudy water, algae blooms, and rising nitrates. Learn the 5 warning signs and exactly how to fix portion sizes fast.
August 19, 2025MaintenancepH Crash: Common Causes and How to Stabilize It
A pH crash is usually triggered by one specific, fixable cause. Learn the most common triggers and how to stabilize aquarium pH without chemical shortcuts.
August 5, 2025EquipmentThe Quarantine Tank Setup That Actually Gets Used
A quarantine tank setup you actually use is a bare 10 to 20 gallon tank with a seeded HOB filter, a heater, and cover. Simple beats elaborate every time.
July 22, 2025MaintenanceControlling Nitrate Without Constant Water Changes
Controlling nitrate without constant water changes means exporting nitrogen, not just diluting it. Learn which methods work and how to match them to your tank.
July 8, 2025BeginnerHow Long Does It Really Take to Cycle a Saltwater Tank?
Cycling a saltwater tank takes anywhere from 2 weeks to 2 months depending on your bacteria source, temperature, and ammonia consistency.
June 20, 2025DiseaseTreating Ich in a Reef Tank Without Killing Your Corals
You cannot safely treat ich in a reef tank with medication. Learn the two reef-safe methods that cure ich without harming your corals, clams, or shrimp.
June 2, 2025MarineWhy Your Alkalinity Keeps Swinging (And Why SPS Hates It)
Alkalinity swings stress SPS corals more than a low but stable number. Learn why dKH fluctuates in reef tanks and how to fix it for good.
May 18, 2025BeginnerAmmonia Spike in a New Tank: What It Means and How to Fix It
An ammonia spike in a new tank is normal during the nitrogen cycle. Learn what causes it, how to fix it safely, and how to prevent fish loss.
May 3, 2025