Lake Kutubu Rainbowfish

[mitch70]

I have seen these online and I am seriously considering purchasing these but trying to stop myself being an impulse buyer and though I would ask for advice/opinions first.

I have a Roma 240 litre tank with an external 306 filter, current inhabitants are

10 x amano shrimp
1 x apple snail
11 x zebra danio
5 x mollies
4 x guppies
5 x bolivian ram
6 x harlequin's

I currently do 25-30 percent weekly water changes - my ph is around 7.5

Can I accomodate these in my aquarium or am I being greedy (was looking for 5).

Thankyou

 

[nmonks]

You're going to need at least 6, and I'd *strongly* recommend more females than males when keeping any Melanotaenia species. If you don't keep this number of fish and more females than males, bullying becomes a very real possibility. It's common for people to "go cheap" and buy 4 or 5 rainbowfish, then over the next year end up with just one dominant male.

Melanotaenia lacustris isn't difficult to keep provided you have hard, alkaline water, but do be aware it dislikes very warm water, so keep at or just below 25 C. This may cause problems in terms of tankmate choices -- harlequins need soft, acidic water for example -- but if you can work around these limitations, they're good community fish. Moving out the harlequins from your current community will be necessary anyway just on account of the mollies and guppies, so you're freeing up some space right there. All else being equal, you could add 2 males and 4 females to this system without problems.

However, I've had trouble with mollies fighting with rainbowfish, so do watch them carefully. So far as I could figure out, the tall backs of the rainbows looked like the raised sailfin of the giant sailfin mollies I was keeping at the time, and the male mollies viewed the rainbows as threatening because of it.

Cheers, Neale

 

[mitch70]

Thankyou for the very quick and informative reply. I will ensure I order 6 (was going to order from sweet knowle aquatics) will specifiy I want 4 female and 2 male.

I will rehome the harlequins - after that I take it I am ok stocking wise but assume this will put me at my max?

 

[nmonks]

Hmm… I don't think so, but I wouldn't add anything else until the tank's been running for a few months and you're sure water quality is within proper parameters. 240 litres is a fair amount of space, and you've mostly got quite small fish, so I don't think you're at the limit yet. You may want to add a couple more rainbows. You don't need twice as many females as males, but it is a good idea to have one or two spare females within a group. So you could go with 3 males and 4 females, for example. Obviously the more females the better, as there's less risk of males becoming combative, but the main thing is to avoid having just two males*, so the one male bullies the other, and also to make sure there are enough males and females for the males to colour up properly.

Cheers, Neale

*Yes, I realise I contradict myself in the previous reply! Wasn't thinking straight.

after that I take it I am ok stocking wise but assume this will put me at my max?

 

[mitch70]

Once again thanks for the quick reply.

I am definatley looking to keep something a bit bigger that is fairly hardy and not too difficult to keep and these seem to fit the bill and they look really good as well.

Will I need to up my water changes as a number of sites state I should be looking at at least 50% every week?

mind some also say Harlequins are suitable tank mates! but that is the reason I always ask here first as much more reliable.

I will also make sure I wait a good while before considering adding anything else to the tank -


Mitch

 

[nmonks]

Most welcome!

Harlequins are fine in terms of personality; but they do prefer soft water, and these rainbows must have moderately hard, basic water to do well. Do review the usual reliable sites: Fishbase, Seriously Fish, etc.

50% a week is good for any fish, but the issue is more about nitrate level than anything else. In an understocked tank you could probably get away with 25% assuming nitrate stayed below 20, 30 mg/l; but in a busier tank, or else if you have high nitrate water right out the tap, then more frequent water changes will be a plus. Because this rainbowfish comes from a lake rather than a river, it doesn't like strong water currents, so getting filtration right might be tricky, and that's another reason why frequent water changes are useful. But with that said, this rainbowfish hasn't proven to be any more delicate than other New Guinean Melanotaenia species.

Cheers, Neale

Once again thanks for the quick reply.

I am definatley looking to keep something a bit bigger that is fairly hardy and not too difficult to keep and these seem to fit the bill and they look really good as well.

Will I need to up my water changes as a number of sites state I should be looking at at least 50% every week?

mind some also say Harlequins are suitable tank mates! but that is the reason I always ask here first as much more reliable.

I will also make sure I wait a good while before considering adding anything else to the tank -


Mitch

 

[mitch70]

More buckets here I come!


would you recommend any other Rainbow fish? from the reserach I have done these seemed to be the hardiest and as a new fish keeper I dont want to push my luck too much.

 

[nmonks]

Rainbows are great fish.

Check out Celebes and Madagascar Rainbowfish, both underrated and versatile. Madagascans are gorgeous when mature.

Three other excellent species:

Melanotaenia parkinsoni
Glossolepis incisus
Melanotaenia boesemani (wild specimens especially)

I've got some Threadfin Rainbows and they're charming; small, a bit delicate immediately after purchase, but otherwise excellent fish for small fish communities.

Cheers, Neale

 

[mitch70]

I've ordered 6 - 2 male, 4 female they arrive on Tuesday - can't wait.