Soft vs Hard Water: Simple Guide for Shrimp & Planted Tanks

When we first get interested in shrimp or planted tanks, everyone talks about:

“Your water must be good.”

Some say you must use RO water.
Some keep shrimp in random tap water and somehow everything is fine.
The rest of us just look at the tap and think:

“Is my water soft? Hard? Is it safe for shrimp and plants or not?”

 

This post is my attempt to answer that in simple language, from the point of view of someone who:

• Doesn’t have cheap RO or distilled water

• Wants to build a natural ecosystem tank

• Uses whatever water is available at home

We’ll keep it practical:

• What soft and hard water actually mean

• Why it matters for shrimp and plants

• How to think about your tap water realistically

Later, in another post, we’ll dive deeper into the “scary numbers”: GH, KH, and TDS.

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1. What Is Hard Water? What Is Soft Water?

Forget shrimp for a moment. Think about your kettle and bathroom.

• If you see white crust on your kettle, shower head, or faucet:
  That’s usually minerals drying out on the surface → often a sign of hard water.

• If soap doesn’t lather well, or it leaves a “film” feeling on your skin:
  That can also be related to water hardness.

In simple terms:

• Hard water = water with more dissolved minerals
  Mainly calcium (Ca²⁺) and magnesium (Mg²⁺).

• Soft water = water with fewer dissolved minerals

You can imagine it like soup:

Type of water	Simple picture
Soft water	Plain soup, almost just warm water
Hard water	Soup with lots of invisible “ingredients” (minerals)

Both are still water. The difference is just how much “stuff” is dissolved inside it.

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2. Why This Matters for Shrimp

Shrimp are basically tiny armored creatures.
Their “armor” (shell) needs minerals to be strong.

They need those minerals to:

• Build and maintain their shell

• Molt properly

• Recover after molting

So for shrimp:

• Too low minerals (very soft water)

  • Can lead to weak shells

  • Molting issues

  • More fragile, sensitive shrimp

• Moderately hard water

  • Often good for Neocaridina (the common, beginner-friendly shrimp)

  • Provides minerals for healthy shells

  • More forgiving for new shrimp keepers

• Very hard water (extreme cases)

  • Still possible to keep hardy shrimp, but you might see more crust on glass and equipment

  • Sensitive species (many Caridina types) may not like it

The key lesson:

For beginner shrimp, we don’t always need super soft water.
We need enough minerals + stable conditions.

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3. Why This Matters for Plants

Plants also care about minerals, but in a different way.

They use calcium, magnesium, and other elements to:

• Build strong cell walls

• Grow healthy new leaves

• Transport nutrients inside the plant

If your water is:

• Extremely soft (almost no minerals)

  • Some plants can suffer deficiencies

  • Leaves may look weak, twisted, or pale

  • You may need to compensate with fertilizers or special salts

• Moderately hard

  • Many common aquarium plants can live and grow just fine

  • Especially in a tank with soil or nutrient-rich substrate

• Very hard

  • Some tough plants still grow

  • Others may struggle or show weird symptoms

  • Algae problems can appear if nutrients get unbalanced

For a natural, low–medium tech planted tank (no crazy high light, no aggressive CO₂), many plants are surprisingly flexible. They care more about:

• Stable conditions

• Enough nutrients

• Not being shocked by sudden changes

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4. Soft vs Hard Water in a “Natural Ecosystem” Tank

A lot of people (including us) are interested in natural ecosystem aquariums:

• Deep or enriched substrate

• Many plants and roots

• Driftwood, leaves, botanicals

• Gentle water flow

• Not too many fish

In this style of tank:

• Soil, wood, and dried leaves can slowly change the character of the water:

  • Adding tannins (brown tea color)

  • Slightly lowering pH over time

  • Creating a more “river or forest stream” feel

• Even if you start with medium-hard tap water, the tank’s environment can make it behave more softly and naturally.

So instead of thinking:

“My water is wrong.”

You can think:

“My tap water is my starting point.
My substrate, wood, and leaves will gently adjust it.
I just need to understand where I’m starting from.”

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5. How to Guess If Your Water Is Soft or Hard (Without a Lab)

Of course, the best way is to test (we’ll talk about GH, KH, TDS in the next article).
But if you don’t have test kits yet, you can still make a rough guess:

Signs of harder water:

• Thick white mineral crust on kettles, faucets, aquarium rims

• Soap doesn’t lather as much and leaves a “draggy” feeling

• Local people often say, “Our water is very ‘keras’ / high in kapur”

Signs of softer water:

• Little to no mineral crust on metal and glass

• Soap rinses off very easily

• In some regions, people mention pipes corroding faster (because water is more aggressive)

You can also:

• Ask your local aquarium shop – many already know if the city water is hard/soft.

• Ask local hobby groups online – “Anyone know the GH/KH of tap water in [your city]?”

Perfect numbers are not needed yet. Just knowing “I’m more on the hard side” or “Mine is quite soft” is already useful when choosing shrimp and plants.

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6. Is Soft Water Always Better?

Short answer: No.

Soft water is not automatically “premium water”. It’s just a different starting point.

• Some advanced shrimp (especially many Caridina varieties) prefer soft water with carefully controlled minerals (usually people use RO water and special remineralizing powders).

• Many popular beginner shrimp (especially Neocaridina) and common fish are perfectly happy in medium to moderately hard tap water.

Problems happen when:

• Water is extreme (super soft with no buffering, or super hard and very unstable), and

• We make sudden changes (large water change with very different water, or using chemicals to push pH hard in one shot).

So for most beginners with normal tap water:

Slightly hard or medium water + stable routine
is usually better than chasing ultra-soft water with random chemicals.

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7. How I Personally Think About My Water

Here’s a simple way I frame it in my head when planning tanks:

A. Shrimp-Only Tank (Neocaridina)

• I accept that my tap water may be medium or slightly hard.

• I make sure to:

  • Dechlorinate it

  • Avoid extreme pH changes

  • Keep temperature stable

• I use:

  • Plants, moss, wood, and leaves

  • Many hiding spots so shrimp feel safe

• I see minerals as a friend: they help with molting and shell health.

B. Planted Community Tank (Shrimp + Small Fish)

• Water must be okay for both shrimp and fish.

• I know baby shrimp will be eaten, so I don’t expect a shrimp “farm” here.

• I focus on:

  • Regular, moderate water changes

  • Not letting hardness or pH swing wildly

  • Providing nutrients for plants (substrate or light fertilizing)

C. Sensitive / Advanced Species

• This is the area where people use:

  • RO or distilled water

  • Precise remineralizer salts

  • Tight control of GH/KH/TDS

• If getting RO or distilled water is expensive or difficult, I simply don’t choose those species yet. I match my livestock to my water, not my water to my wishlist.

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8. Using Your Water as a Guide, Not an Enemy

Instead of fighting your tap water, you can let it guide you:

• If your water is medium to hard:

  • Great for Neocaridina shrimp, many snails, lots of hardy plants.

• If your water is soft:

  • Could be nice for some delicate fish and shrimp, but you may need to be careful with buffering (KH) and stability.

Your tank doesn’t have to look like the perfect YouTube setup with RO units, fancy filters, and expensive salts.

You can still have:

• Healthy shrimp

• Lush plants

• A calm, natural vibe

with imperfect but understood tap water.

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9. What’s Coming Next: GH, KH, and TDS (The “Numbers” Behind Soft & Hard)

In this post, we talked about soft and hard water in human language.

In the next article of this water series, we’ll connect this to the three numbers that usually scare beginners:

• GH – General Hardness → “how much mineral soup?”

• KH – Carbonate Hardness → “bodyguard for your pH”

• TDS – Total Dissolved Solids → “how much stuff is dissolved in total?”

We’ll treat them like three characters with simple jobs, and we’ll see how they relate to soft vs hard water, shrimp health, and planted tanks.

For now, if your tank is running on conditioned tap water and you’re doing your best to keep things stable, you’re already on the right path.

You’re not late.
You’re just building your own ecosystem at your own pace. 🌱🦐

Water Basics Series — Wander Within Life

1. Soft vs Hard Water (You’re here)
2. GH, KH & TDS — The Three Numbers
3. No RO, No Distilled: Can I Still Keep Shrimp?
4. Do We Really Need a Filter?
5. Filters for Shrimp Tanks — Flow • Intake • Media
6. How I Treat Tap Water Before It Enters My Aquarium
7. Pothos as a Natural Filter — Roots in Water, Leaves Above