Stocking a 135 Gallon Aquarium

Hey everyone, my name is Jae! I'm new here and I'm a (sorta) new fish owner. I've been mostly keeping Bettas (3 in 10-15g tanks), but I have one community tank (15g) with cories, shrimp, and neon/ember tetras; so a total of four active tanks. I've run into a bit of a dilemma and I was looking where to ask this info.

Recently I've adopted some albino juvenile redfin (or rainbow) sharks (they're about 2 inches right now) from a friend who couldn't keep them anymore. He wanted to throw them into a local pond because he couldn't keep them anymore, but I took them instead. My friend doesn't know what they are; thought they were catfish, but I looked it up online and eventually figured out they're probably sharks since they don't look my albino cories. Here is a picture of one of them:
View attachment 137222
. My father used to keep an arowana and my mother used to breed fish for food(?) in the past, so I have a 135g tank and a 200g tank at my disposal for when these guys get bigger. My father prefers using the 135g while I'm more partial to the 200g tank (because I've always been told bigger is better right?), but he gets to make the final call at the end of the day. I've been told that Redfins / Rainbows are aggressive towards each other, but a big enough tank may big enough right? Right now, I'm keeping them in a quarantine tank (10g and 15g) but one of them is chilling with my Betta in the 15g tank with plans to move them as soon as the big tank is set up (I'm kinda worried shoving them all into the quarantine tanks so I split them up).

I was thinking that it seemed a bit of a waste to keep only 3 redfins/rainbows in a 135g tank (or 200g) tank (though I'd be willing to keep it at that for them if that's best) and I was wondering if anyone had any ideas what kind of fish would be safe to stock with the rainbow/redfins that won't get hurt/eaten in a 135g tank (minimum, father is on the fence about using the 200g one). Also I have a decent grasp of tank setups, but I've never had a tank this big before. I was wondering what kind of plants/rocks/substrate I should be using to make the sharks feel at home.

Just a footnote, I do live in Indonesia and fishkeeping here is a bit haphazard, pet stores do not typically understand what kind of fish they have or how to care for them (everything I learned is from learning online). Some things are a bit difficult to get here, but I already have all the essentials from ordering online (PH, nitrite/nitrate/ammonia testers, etc) and am willing to get anything else I may need.

Thanks everyone!

They are a kind of catfish, but their appearance often labels them as "sharks". You could probably get away with three of them in either tank, so long as the tanks are long rather than tall. They have sensitive barbels around their mouths, so a sand substrate is best for them. You will want driftwood and rocks to break line of sight, and so they can develop their own territories.

I have one in with Skirt Tetras right now. They are okay with most fish that aren't bottom dwellers, but you don't want any small enough to fit into their mouths either.

Can you check your water GH and pH? If you don't have the test kits, can you check from your water agency website?

If I'm not wrong Indonesian tap water should be soft water.
If your water is soft, you can consider South American and Asian fish.

Indonesia has many fish farms and you can easily find many fish.
By the way, I think your Rainbow sharks are quite aggressive and I have no idea what fish are suitable for them.

If you remove the Rainbow sharks, it will be easier to decide.
For your size of tank, you can consider the Earth eaters though I am not sure their suitability with your Rainbow sharks.

You can refer to my postings about Earth eaters here:

Circus said:

They are a kind of catfish, but their appearance often labels them as "sharks". You could probably get away with three of them in either tank, so long as the tanks are long rather than tall. They have sensitive barbels around their mouths, so a sand substrate is best for them. You will want driftwood and rocks to break line of sight, and so they can develop their own territories.

I have one in with Skirt Tetras right now. They are okay with most fish that aren't bottom dwellers, but you don't want any small enough to fit into their mouths either.

Click to expand...

Oh, I see! My measurements say that the 135 gallon is 48in x 27in x 24in (roughly). Would that be enough space for the sharks to swim around and have their own designated territory? For the driftwood, should I try divide it into say, 3 sections that hopefully may break line of sight? I'll be sure to get some aquarium sand to set up the tank. On the other hand, the 200 gallon tank is 61in x 29in x 26in (roughly).

I read online that sharks get about 4-6 inches big, so I'm guessing no to anything that isn't bigger than 1-2 inches?

Lajos_Detari said:

Can you check your water GH and pH? If you don't have the test kits, can you check from your water agency website?

If I'm not wrong Indonesian tap water should be soft water.
If your water is soft, you can consider South American and Asian fish.

Indonesia has many fish farms and you can easily find many fish.
By the way, I think your Rainbow sharks are quite aggressive and I have no idea what fish are suitable for them.

If you remove the Rainbow sharks, it will be easier to decide.
For your size of tank, you can consider the Earth eaters though I am not sure their suitability with your Rainbow sharks.

You can refer to my postings about Earth eaters here:

90 Gallon Stocking

So, I am going to completely redo my 90 gallon. As it is right now, I can hardly stand to look at the tank, it gives me so much anxiety. I lost all 3 of my goldfish, although the other fish are doing alright. So, once I rehome and shuffle my current bunch around I will have an empty 90 gallon...

www.fishforums.net

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My PH levels are usually hovering around 7, but I'm not so sure about the water softness/hardness thing (I don't think I've ever read that online yet), but I'll be sure to look into that. For all my aquariums I use a special faucet that has distilled water in it, so it's probably soft (according to google at least). I do like the idea of tropical fish though, I've been thinking about rainbow fish or angelfish maybe. Circus (the other commenter) said that he has Black Skirt Tetras (which I've never seen before and are really cute) with his shark. I might stick with his idea and consider non-bottom dwellers.

Unfortunately, removing the sharks is not something I can do. I don't really have any way to rehome them. My friend doesn't want them back and I have no idea how to go about giving them away or selling them (the pet store doesn't want them and I don't know anywhere else to give them to). They're still kids at the moment, I'm hoping to move them to their huge tank as soon as possible and establish boundaries; then adding tankmates so they would grow up 'getting used to them' (is that possibly reasonable)? Earth Eaters look really cool, but I'll have to look around for some because I don't see them in listed in the fish store I usually frequent.

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Thanks everyone for responding, I do really appreciate it. I don't know too much about fish yet, so I'm glad I got some responses here!

With the 4 foot tank, you might be able to do 2 of them, but would need a lot of stuff to break line of sight.

With the extra length and width of the 200 gallon, you could probably get away with having all three in the same tank.

Any non aggressive or semi agressive fish over 2 inches, or that has very tall dimensions, should be fine with them. So any larger tetra species would probably work well. Gourami might work okay with them as well, or angelfish.

Circus said:

With the 4 foot tank, you might be able to do 2 of them, but would need a lot of stuff to break line of sight.

With the extra length and width of the 200 gallon, you could probably get away with having all three in the same tank.

Any non aggressive or semi agressive fish over 2 inches, or that has very tall dimensions, should be fine with them. So any larger tetra species would probably work well. Gourami might work okay with them as well, or angelfish.

Click to expand...

I read online that if you have more than one shark, it might be better to have more than just two (the website I've read said 5 which seems way too much) That way whowever is the dominant shark will have his attention split and won't exhaust the other. This is where I read it from. I will do my best to put lots of hidey holes and driftwood between them to give them the best privacy I can.

I've always liked the look of angelfish, so I'm definitely considering those. And some of the larger tetras.

That makes sense, as it would spread aggression around.

azurajae said:

Oh, I see! My measurements say that the 135 gallon is 48in x 27in x 24in (roughly). Would that be enough space for the sharks to swim around and have their own designated territory? For the driftwood, should I try divide it into say, 3 sections that hopefully may break line of sight? I'll be sure to get some aquarium sand to set up the tank. On the other hand, the 200 gallon tank is 61in x 29in x 26in (roughly).

I read online that sharks get about 4-6 inches big, so I'm guessing no to anything that isn't bigger than 1-2 inches?



My PH levels are usually hovering around 7, but I'm not so sure about the water softness/hardness thing (I don't think I've ever read that online yet), but I'll be sure to look into that. For all my aquariums I use a special faucet that has distilled water in it, so it's probably soft (according to google at least). I do like the idea of tropical fish though, I've been thinking about rainbow fish or angelfish maybe. Circus (the other commenter) said that he has Black Skirt Tetras (which I've never seen before and are really cute) with his shark. I might stick with his idea and consider non-bottom dwellers.

Unfortunately, removing the sharks is not something I can do. I don't really have any way to rehome them. My friend doesn't want them back and I have no idea how to go about giving them away or selling them (the pet store doesn't want them and I don't know anywhere else to give them to). They're still kids at the moment, I'm hoping to move them to their huge tank as soon as possible and establish boundaries; then adding tankmates so they would grow up 'getting used to them' (is that possibly reasonable)? Earth Eaters look really cool, but I'll have to look around for some because I don't see them in listed in the fish store I usually frequent.

--

Thanks everyone for responding, I do really appreciate it. I don't know too much about fish yet, so I'm glad I got some responses here!

Click to expand...

Distilled water has GH tht is almost zero and cannot be used without mixing with minerals or tap water.
Make sure that you mix with your tap water or add some minerals (GH+ salts), and test the GH before using the water.
Probably a GH of 5 is good enough for soft water fish.

You will need to test your GH to prevent GH that is too low or GH swing whenever you change the water.
Too much GH swing is bad for your fish.
Your tank water GH should be almost the same as your new water GH.

If you are looking into Tetras species, look for species that are bigger probably the Congo Tetras, Bleeding Heart Tetras, etc.
Take note that Rosy Tetras/Ornate Tetras are quite similar to Bleeding Heart Tetras but they are smaller and sometime the fish stores will make mistake with their names.

I think Angel fish are probably not so suitable due to their long fins. Their long fins are easily nipped by other fish.

Here are some videos:

azurajae said:

I read online that if you have more than one shark, it might be better to have more than just two (the website I've read said 5 which seems way too much) That way whowever is the dominant shark will have his attention split and won't exhaust the other. This is where I read it from. I will do my best to put lots of hidey holes and driftwood between them to give them the best privacy I can.

I've always liked the look of angelfish, so I'm definitely considering those. And some of the larger tetras.

Click to expand...

5 Sharks ?

If you are talking about Bala Sharks yes ,,, maybe but Rainbow Shark are really aggressive. I once had 3 Rainbow Shark in 200G ... they are good while juvenile when they are fully grown they keep in chasing each other till one day I found one of it laying on the floor ... jumping out of the tank .
Had to remove another one to other tanks and only have one per tank and thats ideal.

azurajae said:

I read online that if you have more than one shark, it might be better to have more than just two (the website I've read said 5 which seems way too much) That way whowever is the dominant shark will have his attention split and won't exhaust the other. This is where I read it from. I will do my best to put lots of hidey holes and driftwood between them to give them the best privacy I can.

I've always liked the look of angelfish, so I'm definitely considering those. And some of the larger tetras.

Click to expand...

That linked info is generally good. The bottom line is, only one Rainbow shark in the tank, not two; a group of five might spread aggression but needs a very much larger tank than either of these. Tankmates must be carefully thought out. Angelfish will not work. Upper swimming robust fish like many of the barbs and danios and larger rainbowfish would be worth considering.

Always research the species thoroughly from a reliable site before deciding. Fish have traits and requirements programmed into their DNA and we must recognize these and provide accordingly. You had these two "sharks" thrust upon you, and it is not your fault in saving them, but it shows how complicated it can be with certain fish.

Lajos_Detari said:

Distilled water has GH tht is almost zero and cannot be used without mixing with minerals or tap water.
Make sure that you mix with your tap water or add some minerals (GH+ salts), and test the GH before using the water.
Probably a GH of 5 is good enough for soft water fish.

You will need to test your GH to prevent GH that is too low or GH swing whenever you change the water.
Too much GH swing is bad for your fish.
Your tank water GH should be almost the same as your new water GH.

If you are looking into Tetras species, look for species that are bigger probably the Congo Tetras, Bleeding Heart Tetras, etc.
Take note that Rosy Tetras/Ornate Tetras are quite similar to Bleeding Heart Tetras but they are smaller and sometime the fish stores will make mistake with their names.

I think Angel fish are probably not so suitable due to their long fins. Their long fins are easily nipped by other fish.

Here are some videos:

Click to expand...

I mix in aquarium salt with my tanks because I read online that'd be good for bettas (I have a 'salt water jar' I have mostly just in case for the quarantine tank) I use and add when needed! I'll have to look into GH thing a bit more. Now that you and Bryon pointed out the things with Angelfish I may reconsider, though larger tetras seem okay.

But I may focus on trying to figure out the shark situations first and then work on any tankmates later.

Dajuyu said:

5 Sharks ?

If you are talking about Bala Sharks yes ,,, maybe but Rainbow Shark are really aggressive. I once had 3 Rainbow Shark in 200G ... they are good while juvenile when they are fully grown they keep in chasing each other till one day I found one of it laying on the floor ... jumping out of the tank .
Had to remove another one to other tanks and only have one per tank and thats ideal.

Click to expand...

Byron said:

That linked info is generally good. The bottom line is, only one Rainbow shark in the tank, not two; a group of five might spread aggression but needs a very much larger tank than either of these. Tankmates must be carefully thought out. Angelfish will not work. Upper swimming robust fish like many of the barbs and danios and larger rainbowfish would be worth considering.

Always research the species thoroughly from a reliable site before deciding. Fish have traits and requirements programmed into their DNA and we must recognize these and provide accordingly. You had these two "sharks" thrust upon you, and it is not your fault in saving them, but it shows how complicated it can be with certain fish.

Click to expand...

That is my biggest worry. I'm not really sure what to do with these three sharks. As a last resort, my mother does have a pond where she raises fish for food (like for eating). It's like 2 meter wide, 4 long meter glass pond. There's a mix of all sorts of different kind of fish there and when they're older, I could release 2 of them there and keep one in tank, but I have no idea if the other fish would be compatible with them at all. I can't be certain of the water quality there either, because even though I tried to explain to my parents about fish care, they don't seem too bothered. There is also a very long waterfall pond on one side of my house (about 1.5 meters wide and 15cm wide) that my father says we could put there, but he's put 2 goldfish in there already (to eat mosquitoes???) and they died. If I do move one of the sharks there, what's their probability of survival? I could post pictures of both.

My father seems content with trying to put them all in a 135g tank. I was considering on top of the 135g tank for one of them, I get 2 more tanks (length wise) and put the other two there. Would Bettas get along with Sharks when they're older? If I say get two 50g tanks (long ones) and move 2 of my bettas into those to 50g tanks, so I would have one 15g (betta), two 55g (Betta + shark), community tank (10g Tetras and peaceful fish), and one 135g (Shark and other fun stuff).

Over the time I've had fish, I have really fallen in love with them and I've started seeing them more than the 'mindless' creatures I used to think them as, but I really don't know what to do with the other 2 sharks. I am looking for ways to rehome them, but I'm not sure it's possible. It breaks my heart knowing that at least 2 of them may not have the quality of life they deserve, but I'm not sure I can spare anymore time adding fish tanks on top of the ones I already have. I wish I had maybe only adopted one of them, but my friend would have tossed the other two in a local pond and I'm not sure if they'll survive there. Maybe I did the right thing in my head, but in the end the fish will just suffer. I'll just have to do my best with what I have, whether it is risking it with 3 in a tank or condemning two of them for the somewhat controlled ponds.

--

Thanks everyone for the replies and helpful advice. They mean a lot to a newish fishkeeper like me. I know I may seem a little irresponsible for having so many fish. I did actually have four bettas at one point (one of them passed away), but I've only ever wanted my one betta Puyo (15g) and my community tank (10g). My mother entered a couple fish raffles online since she 'thought they'd be fun' and won 3 betta fish and basically handed them off to me to take care of. I was really angry at her at the time because she didn't know how much work a single betta fish was and I refused to put them in a 2 liter tank like her friends did. I felt really awful when one of them died, maybe my attention got divided and I didn't have enough time for all of them. I really want to prevent that from happening again.

azurajae said:

I mix in aquarium salt with my tanks because I read online that'd be good for bettas (I have a 'salt water jar' I have mostly just in case for the quarantine tank) I use and add when needed! I'll have to look into GH thing a bit more. Now that you and Bryon pointed out the things with Angelfish I may reconsider, though larger tetras seem okay.

Click to expand...

Actually the minerals (GH+ salt) is totally different from your normal salt.
Don't use salt for your Bettas unless for treatment of diseases. Too much salt for a long period(more than 4 weeks) will damage the fish kidneys.

Here is one example of minerals which is suitable for African cichlids.

It seems to me that your Rainbow sharks are soft water fish based on this website:
The GH require is 36 to 268ppm (about dGH 2 to 15).


You can read the links here to understand more about GH:




By the way, keeping the fish in a pond doesn't mean that it's bad for your fish if your pond is big with a lot of plants.
Fast growing plants like Anacharis Elodea, Hornworts, Cabombas can act as filters for your ponds.
Plants are good to absorb ammonia in your pond/tank.

Or you can put a big outdoor filter for your pond.
Also, make sure that the water is not too warm in the afternoon.
You may need to provide some shades if the water gets too warm.

After much deliberation and planning, I decided that I'm going to release two of my sharks into the smaller waterfall pond so I can monitor their health. There's actually a couple goldfish there already, so I'm going to wait 'til they're a tiny bit bigger so I can keep track of them (though since they're albino I think they'll be easier to spot occasionally). I gave the sharks names so I can keep track of them (Pluto, Moon, and Comet). Pluto (the biggest one) is going to go into the 135g tank while Moon and Comet are going to move into the pond with the goldfish. I have to do some maintenance in the pond (adding some sand and extra hidey-holes / plants), but I feel like this is the best decision after doing much more research and the advice given in this thread.

Thanks so much for the advice here, it's really helped a lot and I hope I'll be able to give these sharks the best quality of life I can.

As for the 135g, I'm probably going to pick out some Rainbow Fish or larger tetras to stock alongside Pluto.

Lajos_Detari said:

Actually the minerals (GH+ salt) is totally different from your normal salt.
Don't use salt for your Bettas unless for treatment of diseases. Too much salt for a long period(more than 4 weeks) will damage the fish kidneys.

Here is one example of minerals which is suitable for African cichlids.

Seachem - Cichlid Lake Salt

www.seachem.com

It seems to me that your Rainbow sharks are soft water fish based on this website:
The GH require is 36 to 268ppm (about dGH 2 to 15).

Epalzeorhynchos frenatum – Rainbow Shark (Labeo frenatus, Epalzeorhynchus frenatus) — Seriously Fish

www.seriouslyfish.com

You can read the links here to understand more about GH:

One moment, please...

The Fish Keeper’s Guide to pH, GH, and KH | Water Chemistry 101

This practical guide for beginners explains what these water chemistry terms mean, when you should test for them, and how to raise or lower them if needed.

www.aquariumcoop.com

Frequently asked questions on lowering hardness

Some fish prefer soft water, and others benefit from softer water for breeding. But how do you make hard water soft, and how do you interpret hardness levels? Matt Clarke explains.

www.practicalfishkeeping.co.uk

By the way, keeping the fish in a pond doesn't mean that it's bad for your fish if your pond is big with a lot of plants.
Fast growing plants like Anacharis Elodea, Hornworts, Cabombas can act as filters for your ponds.
Plants are good to absorb ammonia in your pond/tank.

Or you can put a big outdoor filter for your pond.
Also, make sure that the water is not too warm in the afternoon.
You may need to provide some shades if the water gets too warm.

Click to expand...

Oh, I see! I've always been told that adding a bit of salt to the aquarium is good for their health, but if that's the case I'll do a bigger water change next time to reduce the salt in the water. I looked into the GH and minerals and am looking to see where the best place to buy them is (as well as a test kit otw), though honestly the fish stores here aren't that...robust(?) so I'll have to order them online looks like. I did order a bunch of dried coral(?) I actually just put into the filters (because I was wanting to make a biofilter), and I read that may work?

The good thing about the waterfall pond is that it has a built in filter so I don't need to worry about that, but it needs some substrate on the bottom for the sharks to be comfortable, so I'll be adding some sand and extra plants there. The way it looks like is that it's a cascading pond with plants on the higher levels and it drips down to the lower levels. I'll just be adding the sharks to the lowest levels along with some substrate and extra plants. And this area of the house is completely shaded most of the time, so it shouldn't be too warm (the only time the sun hits it is around the morning/early afternoon).

Thanks so much for the info, Lajos, I'll definitely be adding these to my notes. You're very helpful ^^

By the way, first check your water GH.
If your GH is good enough for your soft water fish, then you don't need any mineral salts.
It will be more convenient not to use the mineral salts.
My tap water GH is 5 which is good for most soft water fish.
So, I don't need to add any mineral salts.

Lajos_Detari said:

By the way, first check your water GH.
If your GH is good enough for your soft water fish, then you don't need any mineral salts.
It will be more convenient not to use the mineral salts.
My tap water GH is 5 which is good for most soft water fish.
So, I don't need to add any mineral salts.

Click to expand...

Got it! That's why I ordered the test kit first. Then I'll see if I need any minerals or anything, but I was just checking online just to make sure there's a way to purchase them in the off chance I do need them.