Fish for hard water
Tap water in most Lithuanian cities runs around 20 °dH. You can soften it — every week, forever, with RO water and a routine — or you can keep fish that already want what comes out of the tap. This is the second list, and it is the easier life.
Why these
Tolerates 18 °dH and above, and its comfortable range already begins at 8 °dH.
75 species

Endler's Livebearer
Poecilia wingei
4.5 cm · 22–29 °C · ≥ 30 l

Guppy
Poecilia reticulata
6 cm · 22–28 °C · ≥ 40 l

Platy
Xiphophorus maculatus
6 cm · 18–26 °C · ≥ 55 l

Colombian Ramshorn Snail
Marisa cornuarietis
5.5 cm · 22–28 °C · ≥ 40 l

Convict Cichlid
Amatitlania nigrofasciata
13 cm · 21–29 °C · ≥ 110 l

Cuckoo Catfish
Synodontis multipunctatus
15 cm · 22–27 °C · ≥ 200 l

Dwarf Petricola Catfish
Synodontis lucipinnis
8 cm · 22–27 °C · ≥ 100 l

Electric Yellow Lab
Labidochromis caeruleus
10 cm · 23–28 °C · ≥ 200 l

Even-spotted Synodontis
Synodontis petricola
13.5 cm · 23–28 °C · ≥ 120 l

Maingano Cichlid
Melanochromis cyaneorhabdos
10 cm · 23–28 °C · ≥ 180 l

Molly
Poecilia sphenops
10 cm · 24–28 °C · ≥ 90 l

Rusty Cichlid
Iodotropheus sprengerae
10 cm · 23–28 °C · ≥ 200 l

Sailfin Molly
Poecilia latipinna
12.5 cm · 20–28 °C · ≥ 120 l

Swordtail
Xiphophorus hellerii
14 cm · 22–28 °C · ≥ 90 l

T-Bar Cichlid
Amatitlania sajica
12 cm · 23–30 °C · ≥ 150 l

Acei Cichlid
Pseudotropheus acei
13 cm · 23–28 °C · ≥ 200 l

Blue Dolphin Cichlid
Cyrtocara moorii
25 cm · 24–28 °C · ≥ 350 l

Boesemani Rainbowfish
Melanotaenia boesemani
11 cm · 22–30 °C · ≥ 150 l

Borleyi (Redfin Hap)
Copadichromis borleyi
20 cm · 23–28 °C · ≥ 300 l

Brevis Shell Dweller
Neolamprologus brevis
6 cm · 23–27 °C · ≥ 40 l

Brichardi (Fairy Cichlid)
Neolamprologus brichardi
10 cm · 22–27 °C · ≥ 110 l

Calvus Cichlid
Altolamprologus calvus
13 cm · 23–27 °C · ≥ 200 l

Celebes Rainbowfish
Marosatherina ladigesi
8 cm · 22–28 °C · ≥ 90 l

Cobalt Blue Zebra
Metriaclima callainos
13 cm · 24–28 °C · ≥ 200 l

Compressiceps Cichlid
Altolamprologus compressiceps
13 cm · 24–28 °C · ≥ 200 l

Cylindricus Cichlid
Neolamprologus cylindricus
11 cm · 23–28 °C · ≥ 110 l

Cyprichromis
Cyprichromis leptosoma
12 cm · 23–27 °C · ≥ 250 l

Electric Blue Ahli
Sciaenochromis fryeri
18 cm · 24–28 °C · ≥ 280 l

Ellioti Cichlid
Thorichthys ellioti
15 cm · 22–28 °C · ≥ 200 l

Featherfin Squeaker
Synodontis eupterus
20 cm · 22–27 °C · ≥ 200 l

Five-bar Cichlid
Neolamprologus tretocephalus
15 cm · 23–27 °C · ≥ 200 l

Golden Julie
Julidochromis ornatus
8 cm · 23–27 °C · ≥ 90 l

Hongi Cichlid
Labidochromis sp. 'Hongi'
12 cm · 22–28 °C · ≥ 250 l

Johanni Cichlid
Melanochromis johannii
12 cm · 23–27 °C · ≥ 200 l

Lemon Cichlid
Neolamprologus leleupi
10 cm · 23–27 °C · ≥ 110 l

Livingstoni
Nimbochromis livingstonii
25 cm · 24–28 °C · ≥ 350 l

Malawi Eyebiter
Dimidiochromis compressiceps
25 cm · 23–28 °C · ≥ 350 l

Marlieri Cichlid
Julidochromis marlieri
13 cm · 23–27 °C · ≥ 110 l

Multifasciatus Shell Dweller
Neolamprologus multifasciatus
4.5 cm · 24–27 °C · ≥ 45 l

Ocellatus Shell Dweller
Neolamprologus ocellatus
6 cm · 23–27 °C · ≥ 40 l

Peacock Cichlid
Aulonocara stuartgranti
13 cm · 23–28 °C · ≥ 280 l

Powder Blue Cichlid
Chindongo socolofi
11.5 cm · 23–28 °C · ≥ 200 l

Red Empress
Protomelas taeniolatus
15 cm · 23–28 °C · ≥ 250 l

Red Rainbowfish
Glossolepis incisus
15 cm · 22–30 °C · ≥ 180 l

Red Zebra Cichlid
Maylandia estherae
13 cm · 24–28 °C · ≥ 200 l

Redhead Cichlid
Vieja melanura
35 cm · 24–30 °C · ≥ 400 l

Regan's Julie
Julidochromis regani
15 cm · 23–27 °C · ≥ 180 l

Rostratus
Fossorochromis rostratus
28 cm · 23–29 °C · ≥ 450 l

Saulosi Cichlid
Chindongo saulosi
9 cm · 23–28 °C · ≥ 200 l

Similis Shell Dweller
Neolamprologus similis
5 cm · 23–28 °C · ≥ 45 l

Star Sapphire
Placidochromis phenochilus
25 cm · 23–28 °C · ≥ 450 l

Sunshine Peacock
Aulonocara baenschi
13 cm · 22–28 °C · ≥ 200 l

Taiwan Reef Cichlid
Protomelas sp. Steveni Taiwan
16 cm · 24–28 °C · ≥ 300 l

Turquoise Rainbowfish
Melanotaenia lacustris
11 cm · 20–26 °C · ≥ 150 l

Venustus (Giraffe Cichlid)
Nimbochromis venustus
25 cm · 23–28 °C · ≥ 350 l

Wrestling Halfbeak
Dermogenys pusilla
7 cm · 23–29 °C · ≥ 80 l

Zebra Mbuna
Maylandia zebra
13 cm · 22–28 °C · ≥ 200 l

Auratus Cichlid
Melanochromis auratus
11 cm · 22–28 °C · ≥ 400 l

Bumblebee Cichlid
Pseudotropheus crabro
13 cm · 24–28 °C · ≥ 250 l

Bumblebee Goby
Brachygobius doriae
4 cm · 22–29 °C · ≥ 40 l

Demasoni Cichlid
Chindongo demasoni
8 cm · 23–28 °C · ≥ 200 l

Duboisi Tropheus
Tropheus duboisi
12 cm · 23–27 °C · ≥ 300 l

Elongate Mbuna
Pseudotropheus elongatus
13 cm · 23–28 °C · ≥ 250 l

Figure-8 Puffer
Dichotomyctere ocellatus
8 cm · 22–28 °C · ≥ 75 l

Frontosa
Cyphotilapia frontosa
33 cm · 23–27 °C · ≥ 450 l

Goby Cichlid
Eretmodus cyanostictus
8.5 cm · 24–28 °C · ≥ 110 l

Kenyi Cichlid
Maylandia lombardoi
15 cm · 24–28 °C · ≥ 250 l

Malawi Hawk
Aristochromis christyi
30 cm · 23–27 °C · ≥ 450 l

Sand-sifting Xenotilapia
Xenotilapia spilopterus
10 cm · 23–27 °C · ≥ 250 l

Silver Moony
Monodactylus argenteus
25 cm · 24–28 °C · ≥ 450 l

Threadfin Petrochromis
Petrochromis trewavasae
18 cm · 23–27 °C · ≥ 450 l

Tropheus
Tropheus moorii
14 cm · 23–27 °C · ≥ 300 l

Green Spotted Pufferfish
Dichotomyctere nigroviridis
15 cm · 24–28 °C · ≥ 150 l
Dogtooth Cichlid
Cynotilapia afra
10 cm · 23–28 °C · ≥ 200 l
Rubber Lip Pleco
Chaetostoma formosae
10.5 cm · 18–26 °C · ≥ 110 l
Which of these go together?
A list tells you what is possible on its own. Whether three of them share a tank without one eating another — and whether your volume, temperature and hardness actually allow it — is what the planner works out.
Open the planner