The Alkaline Tank

[elmer]

There are actually quite a few (freshwater) fish, which, assuming you're not going to breed them, can, on paper at least, tolerate pH 8, although for many of them this is the upper limit.

(Collected from the index on this site)

A:
Afra Cichlid ([Only Registered Users Can See Links.])
Archerfish ([Only Registered Users Can See Links.])
Argus Fish ([Only Registered Users Can See Links.])
Aulonocara Maulana ([Only Registered Users Can See Links.])
Aulonocara Benga ([Only Registered Users Can See Links.])
Azureus Cichlid ([Only Registered Users Can See Links.])

B:
Badis ([Only Registered Users Can See Links.])
Bala Shark ([Only Registered Users Can See Links.])
Baram Snakehead ([Only Registered Users Can See Links.])
Barca Snakehead ([Only Registered Users Can See Links.])
Banded Bichir ([Only Registered Users Can See Links.])
Barred Sorubim ([Only Registered Users Can See Links.])
Beauty Mouthbrooder ([Only Registered Users Can See Links.])
Bengal Danio ([Only Registered Users Can See Links.])
Black Ghost Knife ([Only Registered Users Can See Links.])
Blackskirt Tetra ([Only Registered Users Can See Links.])
Blue?/Gold Gourami ([Only Registered Users Can See Links.])
Black Small Fighter ([Only Registered Users Can See Links.])
Blind Cavefish ([Only Registered Users Can See Links.])
Bloodfin Tetra ([Only Registered Users Can See Links.])
Blue Acara ([Only Registered Users Can See Links.])
Blue Convict Cichlid ([Only Registered Users Can See Links.])
Bream ([Only Registered Users Can See Links.])
Bristlenosed Catfish ([Only Registered Users Can See Links.])
Buenos Aires Tetra ([Only Registered Users Can See Links.])
Bulldog Pleco ([Only Registered Users Can See Links.])

C:
Celebes Halfbeak ([Only Registered Users Can See Links.])
Chilumba ([Only Registered Users Can See Links.])
Clown Knife Fish ([Only Registered Users Can See Links.])
Cockatoo dwarf Cichlid ([Only Registered Users Can See Links.])
Compressed Cichlid ([Only Registered Users Can See Links.])
Congo Blackfin ([Only Registered Users Can See Links.])
Convict Cichlid ([Only Registered Users Can See Links.])
Cortes Swordtail ([Only Registered Users Can See Links.])
Crystel Eyed Catfish ([Only Registered Users Can See Links.])

D:
Demasoni Cichlid ([Only Registered Users Can See Links.])
Duckbill Catfish ([Only Registered Users Can See Links.])
Dwarf Gourami ([Only Registered Users Can See Links.])
Dwarf Livebearer ([Only Registered Users Can See Links.])
Dwarf Loach ([Only Registered Users Can See Links.])
Dwarf Snakehead ([Only Registered Users Can See Links.])
Duboisi Cichlid ([Only Registered Users Can See Links.])

E:
Electric Blue Hap ([Only Registered Users Can See Links.])
Electric Yellow Lab ([Only Registered Users Can See Links.])
El Quince Swordtail ([Only Registered Users Can See Links.])

F:
Firebird Cichlid ([Only Registered Users Can See Links.])
Firemouth Cichlid ([Only Registered Users Can See Links.])
Flame Tetra ([Only Registered Users Can See Links.])
Flier Cichlid ([Only Registered Users Can See Links.])
Freshwater Barracuda ([Only Registered Users Can See Links.])
Freshwater Barracuda ([Only Registered Users Can See Links.]) (species 2)
Frontosa Cichlid ([Only Registered Users Can See Links.])

G:
Giant Danio ([Only Registered Users Can See Links.])
Gold Gourami ([Only Registered Users Can See Links.])
Gold Mixteco ([Only Registered Users Can See Links.])
Grant's Peacock cichlid ([Only Registered Users Can See Links.])
Gray Bichir ([Only Registered Users Can See Links.])
Green Puffer ([Only Registered Users Can See Links.])
Green Terror Cichlid ([Only Registered Users Can See Links.])
Guppy ([Only Registered Users Can See Links.])

H:
Halfbeak ([Only Registered Users Can See Links.])
Heller's Cichlid ([Only Registered Users Can See Links.])
High Backed Pygme Swordtail ([Only Registered Users Can See Links.])
Hikari Danio ([Only Registered Users Can See Links.])
Hoplo Catfish ([Only Registered Users Can See Links.])
Horsefaced Loach ([Only Registered Users Can See Links.])

I:
Indian Glassfish ([Only Registered Users Can See Links.])
Inle Snakehead ([Only Registered Users Can See Links.])

J:
Jack Demspey Cichlid ([Only Registered Users Can See Links.])
Javan Mouthbrooding Fighting Fish ([Only Registered Users Can See Links.])

K:
Kadango Cichlid ([Only Registered Users Can See Links.])
Keyhole Cichlid ([Only Registered Users Can See Links.])

L:
Leopard Danio ([Only Registered Users Can See Links.])

M:
Madagascar Rainbowfish ([Only Registered Users Can See Links.])
Maison's Peacock ([Only Registered Users Can See Links.])
Malawi Eyebiter ([Only Registered Users Can See Links.])
Malebo Puffer ([Only Registered Users Can See Links.])
Mbu Puffer ([Only Registered Users Can See Links.])
Montezuma Swordtail ([Only Registered Users Can See Links.])

N:
Northern Platy ([Only Registered Users Can See Links.])

O:
One Spot Mouthbrooder ([Only Registered Users Can See Links.])
Orange Finned Danio ([Only Registered Users Can See Links.])
Ornate Bichir ([Only Registered Users Can See Links.])
Otocinclus Catfish ([Only Registered Users Can See Links.])

[elmer]

P:
Pearl Danio ([Only Registered Users Can See Links.])
Pearl Gourami ([Only Registered Users Can See Links.])
Penguin Tetra ([Only Registered Users Can See Links.])
Peppered Corydoras ([Only Registered Users Can See Links.])
Pictus Catfish ([Only Registered Users Can See Links.])
Platy ([Only Registered Users Can See Links.])
Powder Blue Cichlid ([Only Registered Users Can See Links.])

R:
Red Empress Cichlid ([Only Registered Users Can See Links.])
Red Eyed Tetra ([Only Registered Users Can See Links.])
Red Zebra ([Only Registered Users Can See Links.])
Rose Danio ([Only Registered Users Can See Links.])

S:
Sabretooth Tetra ([Only Registered Users Can See Links.])
Sailfin Molly ([Only Registered Users Can See Links.])
Sheepshead Swordtail ([Only Registered Users Can See Links.])
Siamese Fighting Fish ([Only Registered Users Can See Links.])
Sieve Cichlid ([Only Registered Users Can See Links.])
Silver Datnoid ([Only Registered Users Can See Links.])
Snakeskin Gourami ([Only Registered Users Can See Links.])
Spike Tail Platy ([Only Registered Users Can See Links.])
Speckled Platy ([Only Registered Users Can See Links.])
Spotted Green Puffer ([Only Registered Users Can See Links.])
Spotted Talking Catfish ([Only Registered Users Can See Links.])
Sterlet ([Only Registered Users Can See Links.])
Swordtail ([Only Registered Users Can See Links.])
Swordtail Characin ([Only Registered Users Can See Links.])

T:
Tramitichromis intermedius ([Only Registered Users Can See Links.])
Tricolor Cichlid ([Only Registered Users Can See Links.])
(edit: removed Twin Spot Flag Cichlid)
Turquoise Cichlid ([Only Registered Users Can See Links.])

U:
Umbie ([Only Registered Users Can See Links.])
Upland Swordtail ([Only Registered Users Can See Links.])

W:
West African Lungfish ([Only Registered Users Can See Links.])
Western Mosquitofish ([Only Registered Users Can See Links.])
White Cloud Mountain Minnow ([Only Registered Users Can See Links.])
Wolf Fish ([Only Registered Users Can See Links.])

Y:
Yellow Swordtail ([Only Registered Users Can See Links.])

Z:
Zebra Danio ([Only Registered Users Can See Links.])
Zebra Loach ([Only Registered Users Can See Links.])

[elmer]

Surprises:
There's only one rainbowfish species in there. Some swordtails and platies don't make the cut. Some tetras do make the cut.

[Lady Hobbs]

Interesting write-up. Thanks for posting it.

Some may not agree with the entire list but it does give a good idea for those who do have higher pH levels and not sure what can go with their pH.
I look everything up on a compatibility list which gives what water values most prefer but listed makes it easier.

[elmer]

You're welcome. It's just a start, and is only based on this site. Please shout out anything you'd like to add or disagree with below, everyone.

I did it for myself so I could have a quick start looking for another fish for my own tank. I am looking for two or three small top swimmers to go with my keyhole cichlids.

My LFS says rainbowfish are great for our local alkaline water, but the Internet profiles seem to disagree with that for most rainbowfish species. The only one that may be okay for me, according to the Internet, is the Celebes rainbowfish. I am considering various other things like mollies, platies and swordtails.

You can't take online profiles as gospel, or believe everything the LFS says. Oh well, more information is better at least.

The keyholes are enjoying their new home so far; see my blog.

[Lady Hobbs]

It's not that you can't believe LFS so much as you can't believe everything you read online in different sites as well. All is written on the belief of that particular writer. The compatibly sites are something else. One state some fish grow HUGE and other sites claim that same fish "in captivity" grow to half of that stated. Others will name two or three fish that go well together and another will list them together as forbidden.

It can be confusing so it's always good to get several sites to compare information.

Some fish stores have very good personel and know what they are talking about. Some are not so hot.......like the sites.

I'm not surprised that rainbows are not there. They like planted amazon tanks. Of course what our fish like and what they get are two different things. But I am very anxious to get some of them.

I have marked your thread as a sticky. I think it's great information and needs to be marked.

[troy]

Thanks for taking the time to post all of that elmer.

[elmer]

Thanks for taking the time to post all of that elmer.You're welcome.
I should mention that I was inspired to avoid trying to modify the pH of my tap water by this article:
Water Chemistry, For Dummies ([Only Registered Users Can See Links.])
Particularly this part: Fish can adapt to a stable pH that is reasonably far outside their natural range, but fish can not adapt to a changing pH regardless of its value.
(......)
Fortunately, fluctuating pH is not a problem if you use Calgary tap water and follow a proper water-change schedule. Calgary’s water is very well buffered to a pH of about 8.2; which is certainly a high pH for most tropical fishes (at least those from Asia and South America) but at least its stable
To make a long story short, my reaction was, "phew! I've got enough to learn, and enough habits to develop, without worrying about trying to create a stable pH of 7. Now, what fish would be good candidates ...."

[Lady Hobbs]

Always best to work with the water you have to work with to avoid problems.

[elmer]

Next thing we need to do - add a list of plants to this thread.

[shockshockshad]

I see that harlequin rasboras aren't there. I thought they were pretty hardy, so can they be kept in 7.8 to 8 water? They are kind of like tetras and elmer said that some tetras make the cut.....

[Lady Hobbs]

Since this information is coming from what William has already given us the information for, I will unstick this.

[elmer]

I see that harlequin rasboras aren't there. I thought they were pretty hardy, so can they be kept in 7.8 to 8 water? They are kind of like tetras and elmer said that some tetras make the cut.....They're not there because their profile is not on this site. As Hobbs alluded to, I only linked to profiles that are on this site. Perhaps you should solicit in the Tetras forum ([Only Registered Users Can See Links.]) for someone to submit a profile. Personally I think this should be expanded into an article. I don't have the time, or the qualifications, unfortunately.