cuteusagi

Hi everyone!! It may be time that our rainbow shark, Maurice, pass along to another tank. He is the oldest fish in our tank, at about 7 months, and is picking on all our fish. Here's our tank setup first (with approx. current sizes):
-29 gallon
-1 rainbow shark (about 3 inches)
-6 Zebra danios (range from 1/2 an inch to an inch - a young group)
-1 Red Crown Ram (about 2 inches)
-1 Angelfish (about 1.5 inches right now)

Our water chemistry is good, with ammonia, nitrate, and nitrite levels all at 0. The water temperature is a little on the high side (around 80-82) and the pH is also a little high (around 7.6).

For the first few days after adding the ram and the angelfish, the tank seemed alright. Beginning mostly today, the rainbow shark has been chasing all the fish, especially the ram. Sometimes he only chases them when they are near him, sometimes he swims to the opposite side of the tank just to chase them. He had chased the danios in a similar manner, but not frequently and usually when only defending his algae wafer.

The ram is taking most of the attack from the rainbow, and while he never nips, I know that it is still causing quite a bit of stress in the tank. Is there anything I can do to reduce the stress, or will the rainbow shark have to go? There are a few fish stores near us that would be willing to take him in, and right now I'm thinking that's the only option.

Any other opinions on the matter? I just hate to see our beautiful ram and angel getting chased all over the tank because of the recent behavior of our rainbow shark!!!

Chief_waterchanger

I would suggest either moving the rainbow shark to another tank (if available) or getting rid of it.

Trpimp147

you could do that or you can try and rearange your decor in the tank and add a little more hiding that usly helps out with aggression. thats all i had to do with my cichlids

COBettaCouple

yea, if you take the rainbow out and rearrange the tank and reacclimate the rainbow to the tank then let him back in you can see if the "time-out" treatment will work on him. also, would you be able to give the other fish more hiding places and/or plants? if all that fails, then another home/tank might be needed for him.

simpleton

I concur. When you have aggressive fish in your tank, it is advisable that you rearrange the tank when introducing new fish. If that fails, then you will need to find a new home for someone.

Isabella

Here is what www.AquariumLife.net says about the Rainbow Shark: "The Rainbow Shark can be kept in a large community tank if there is plenty of cover to hide in. This larger fish is too aggressive for beginners. Very closely related to the Red Tailed Black Shark. Hollows and hiding places are recommended. Only one Rainbow Shark should be kept in each tank as they are intolerant of their own species. Also try not to keep Rainbow Sharks with Red Tailed Black Shark as they will also fight." ( http://www.aquariumlife.net/profiles...ark/100090.asp ) The website also says that a minimum tank size for this fish is 55 gallons, and that it grows up to 6".

As for the Angelfish and the Ram in a 30 gallon tank, they're OK in there "size-wise". But Angelfish and Rams can become aggressive toward each other as they grow too. They're both Cichlids. In order for Angels and Rams to live in peace, it's best to have them in a large tank with lots of hiding spots (such as plants, driftwood, caves, etc ...) so that in case one of them gets aggressive, the other one has the space to run away and the hiding spots to hide. Your Angel is still young as is the Ram (I presume) so you still have some time before you get a larger tank. That is, if you want a larger tank.

cuteusagi

Thank you all so much for the wonderful replies!!! I really appreciate all your input. I'm including some pictures with this post so you can see what the tank and some fish look like. Hope you enjoy!!

We've tried rearranging the tank and giving the rainbow shark some "time out" a little while ago (in a smaller tank with different tank-mates). It didn't help one bit, and if anything he was a little more aggressive after that. I would hate to do that again and have it be worse than it is now. As for hiding places, there are 3 that he very much enjoys and stays in most of the time. It has nice shade and is quite hidden. Most of the fish don't even know he's there when he is in one of his spots. In the last few days (especially after checking this evening) he is actively swimming through the whole tank, from top to bottom, and was pretty non-aggressive while doing so except for a few chases of the danios and once with the ram. He is still most aggressive while defending his algae wafer, as he likes to nibble on it over a brief period of time. Our current plan of action will be placing him in a smaller tank starting tomorrow morning with the intention of giving him to a friend or to a trusted lfs.

Would the angelfish and the ram really pose a problem? My lfs sold us both fish together, and ever since we put them in the tank, they like to swim together (but not all the time) and are extremely peaceful. The angelfish especially is non-aggressive all the time, even during feeding (he stays in the middle of the tank and catches food as it falls). The ram is also very docile and we love to watch him swim!! He even comes up to the front of the tank when we come to see him!!!

Thanks again for all the help and input!!

Wolfman

Well this time when you rearrange buy some more plants tall ones and makes some blinding spot where the fish can't see the other side of the tank it not only calms the aggression it will slow him down when wants to attack and chase.

COBettaCouple

if another tank's not an option for now, i think that tall plants and more hiding spots could be helpful maybe. perhaps even a tank divider if all else fails.

http://www.drsfostersmith.com/produc...04+113149&va=1 - maybe some of the big plants here along a divider? maybe not an ideal solution, but if it comes down to keeping the rainbow shark from killing the other fish..

cuteusagi

Well, we moved the rainbow shark into a smaller tank - took quite a bit to get him out of the big tank. We put him in, and he is swimming upside down and in barrel-rolls, and looks very disoriented. I've never seen a fish swim like this, and we don't want to kill him - just move him until we can get him to a fish store. Any ideas? We're at a loss on this one!!!!

cuteusagi

Nevermind - our strong Maurice has passed on - it was only about 10 minutes after moving him that he went downhill. Thankfully, the other fish in the tank are doing very well, and even though they experienced the stress through trying to get the rainbow out of the tank, they look very happy. Here's to Maurice!!!!

simpleton

Sorry to hear about Maurice. I'm toasting a cold Budweiser to him right now...Thanks for the photos of the tank and your Angel & Ram...Beautiful fish. The tanks also looks great. I would however, suggest some more plants (Tall ones) and possibly a bridge or another type of cave. It's always nice to have some hiding places for some of your fish. I have 2 very aggressive fish (a male and female African Kenyi) in my 30 gal long with a lone Male Kirb (another Cichlid...well almost) and I need plenty of hiding spaces for the Krib and the female Kenyi. It works nicely with some very tall plants in the back corners and some cave structure. Just some thoughts but your tank and fish look great! Best of luck moving forward. I've attched a photo of my tank for yoru review. Another thought would be to add an outside backdrop to help the fish blend in when hiding in the corners. I truly believe the background helps make my tank look alot more busy than it actually is...it also helps conceal the fish.