aggressive giraffe catfish with RTC (+new tankmate)

njd

Feeder Fish
Original poster
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Sep 28, 2019
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HI,

I have a 2000 litre (7x4) tank with 3 giant grouami (about 2 ft each), 1 RTC (about 18 inches) and 1 Giraffe cat (about 26 inches).

The gouramis get along great (odd bit of chasing at meal times but no real aggression).

I have noticed over the last few months that the giraffe is becoming increasingly aggressive towards the RTC. Every time the RTC comes out of his corner the Giraffe charges at him and headbutts him until he goes back to his corner. He isn't doing much damage as he hasn't got a proper mouth/teeth etc.

He is fine with the giant gourami he just doesnt like the RTC.

Is there anything I can do?

I have anyway been thinking about possibly adding 1 or 2 more cats to tank - would this possibly spread the agression?. I have got a widehead catfish (clarotes laticeps) about 20 inches for sale near me or possibly another similar sized red tail. - what do you think of these as suitable tankmates? I am consious of overcrowding but think that 1 more cat should be ok.

Should I try and rehome the giraffe if it continues?

btw...i know my tank is not big enough for a red tail for life, however I am currently looking into having a pond built. If this does not work out I have a close friend with a big pond who is able to rehome.
 

aroijuana

Exodon
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Jan 24, 2018
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NJ
I would add the widehead.. The giraffe has taken dominance of the tank and there's no other cat to compete/spread aggression. You could try a pleco along with the widehead aswell but I wouldn't do multiple rtc's personally.
 

Fishman Dave

Dovii
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Nov 14, 2015
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Three 2ft giant gourami in a 7x4 with minimal aggression is firstly a surprise for me. I can only assume all are females.
The giraffes do tend to get a little aggressive over 2ft in my experience and they do get grumpy, owning space they think is theirs, but as I have 2 this aggression tends to be kept between them. I have not known red tails to be "agressive" as such and are usually laid back in my experience, so your problem is also that the red tail may never hold his own.
Rather than add another cat to the tank I would first try adding something to break up the bottom area into more defined territories, large bogwood, branch or even some sort of cave cover for the redtail, although anything will have to be substantial. would also be interesting to see what was going on after lights out when both cats would be more active.
Adding more cats could also just cause more problems right now.
As you mention, the red tail won't live forever in that tank so you need to decide if keeping him and building a pond is a reality, as smaller ones are generally easier to rehome if not, even to friends ( transporting a 2 ft or bigger fish is not fun!)
I have a clarotes laticeps of around 2ft for sale near me also however it is listed as extremely human friendly and not aggressive at all. This is not a catfish I have much experience of, but if that's how they are then this could be another cat getting picked upon unless the giraffe can be given only a defined part of the floor space to own.
7x4 is a good size tank - however you already have good size adult fish in most cases, only the red tail is still a baby and potentially more of a target, maybe swap out the red tail for the semi adult clarotes?
 

thebiggerthebetter

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I'd not add any more fish but rather remove some and lighten the bioload. Unless your filtration setup doubles or more the water volume of the tank and your turnover is more than 5x an hour, that is more than 10,000 liters an hour, I think:

(1) you have already far exceeded the crude rule of thumb of 1 cubic inch of fish per gallon,
(2) it is impossible for you to keep ammonia and nitrite at zero ppm (as measured by a liquid test tube kit) at all times, especially after feedings,
(3) you probably have problems with an unstable pH and too low a carbonate hardness KH,
(4) keeping adequate DO is a struggle for you, which you may or may not even know,
(5) you are teetering on the brink of a disaster with such a high bioload per gallon.

I am speaking from experience. I have sometimes comparable bioload per gallon in my tanks but my saving grace are sumps of thousands of gallons, a 10x water turnover in my tanks, vigorous aeration, and a continuous water change of 100% every 6-7 days.
 

njd

Feeder Fish
Original poster
MFK Member
Sep 28, 2019
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Hi all,

Thanks for your replies.

In terms of water quality, that isn't an issue as I have good filtration but most importantly I am lucky enough to have an automatic water change system that changes 5 - 10 % of the water every 4 hours. I know this is excessive however the fish seem happy and every test I have ever done has never shown any issues.

In regards to the suggestion of adding a piece of wood for the RTC to have somewhere to hide, there is already a very large piece of wood in there, that is where he hides. As long as he is there the giraffe doesn't go near him, however whenever he comes out the giraffe charges at him.

Based on your suggestions I am now debating whether to move on the RTC sooner before he gets to big to move easily. I think I may add the widehead and see how he fares with the Giraffe, I suppose if he has a hard time then that would indicate any cat I add will have a tough time and therefore maybe best to move on the Giraffe to somebody with a big pond to give him more space or a tank where he will be the only fish?

What do you think about any of the the following for my tank as alternatives to the widehead:

Apurensis Jelly Cat (Look cool, relatively inactive so will eat less frequently and less of a bioload strain - but possibly aggressive)
Megalodorus Uranoscopus ( relatively inactive and smaller biload strain and well armoured to protect against giraffe 'headbutts')
leiarius marmoratus
leiarius pictus

Thanks
 

thebiggerthebetter

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A 100% WC every 2-4 days will not help you when you need instant dilution of the produced toxins and their denitrification. Sufficient water volume, biofilter, and WC all serve different purposes and neither can help much with any other. I wanna believe your words but a part of me thinks that it is possible you don't measure your water right or at the right times, or haven't measured it enough. Are your ammonia and nitrite readings firmly at zero ppm by a liquid test kit even after a feeding?

All the catfish you are thinking of may work in your community. However, I remain sceptical of your water quality.
 
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njd

Feeder Fish
Original poster
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Sep 28, 2019
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I test 1 or 2 times a month and usually nitrates are not even measurable. I use both API and JBL test kits.

I do like to follow advice though and so I will test an hour after feeding for the next couple of days and I will let you know the results.

Based on everybodys responses - would it be best if i rehomed both the RTC and the giraffe and possibly replaced with 2-3 more sedentary catfish that only require feeding say once a week and therefore much lower on the bioload? (maybe a group of megalodorus uranascopus?)

The 3 gourami get along great and I gather it is rare to have 3 that live peacefully so I am keen to keep them. However I would like some other fish too

Thanks
 

thebiggerthebetter

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Yes, the gouramy situation is indeed exceptional. Good thing is that gouramy usually or often don't pay attention to smaller, dissimilar fish, so you don't need to necessarily get large growing tank mates.

All the catfish you are listing grow large and the bioload will be defined by that, not so much by how much or how often they feed, because the latter is comparable for all of them. If their care is right and they are comfortable, apurensis and irwini catfish eat as much as any of the Leiarius or even RTC at the same size.

Are your ammonia and nitrite readings firmly at zero ppm by a liquid test kit even after a feeding?
You are new here and IDK your level of expertise. Please read and reply more carefully, if you will.


Nitr"a"te does not equate nitr"i"te and even less so equate ammonia,

the two of your most important and basic tests, along with the pH, which you should measure too - of your tap water and of your tank water, if vastly different, your carbonate hardness KH is not coping with the bioload; same if pH of the tank water is not stable. Nitrate is of little concern altogether and is of no concern in your situation of exceptional WC.
 
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