Question about Monos and general Brackish

[Rannoch]

Hello, I'm rather new to this hobby and i've started a brackish tank as sort of a stepping stone to maybe marine tank and to have something rather different. Its been a challange just to find brackish fish but currently I have the following:
2 Columbian Sharks
3 Mollies
2 Green Scats
3 Mono Argen.

These are all housed in my 55g aquarium which some people will probably harass me will not be big enough but if all my fish survive to grow to a rather large size then I could always get a bigger aquaruim.

My first question is about the monos.
I have one mono that is really aggressive. He/she basically rules the tank. He/she doesn't really bother the scats or the columbian sharks but bothers the mollies a bit and the other monos a lot. My other two monos are so scared that one hides almost permantely behind the heater and the other behind the filter. Is there anything that can be done about this aggression and is this really an issue?

My second question is about plants. I've read various suggestions about plants to keep but there seems to be a lot of discrepancy about which plants can be actually kept. Currently my water is at 1.010 SG, and I have a java fern. I use to have this fern in the freshwater aquarium and it did fine there. Its been in this tank for about two months and I'm not really sure if its going to live or die. Many of the leaves are still bright green but several have turned an off green yellowish colour. It is extremely unlikely I will find a store that actually sells a plant that been in brackish water, I'm wondering if anyone has a good suggestion for plant that I can try to bring into brackish water and how long it should take to move it from freshwater to brackish.

My third question is about substrate. Currently I am just using regular aquarium gravel. Should I be using marine sand / argonite? I kinda prefere the dark gravel I have as it makes the fish more colourful. But I'm willing to make sacrifices if I can actually get some green from various plants.

Michael

[Pufferpunk]

Why would you assume all your fish would not survive to grow to a rather large size? With the right conditions & plenty of water changes, all your fish should grow quite large--enough for about 200g.
What are your water paremeters? pH should kept steady, around 8. Usually that is dome by using aragonite sane or crushed coral.

[brackeeper75]

IMO...
Go with plastic plants! Thery are much easier to take care of! At this SG neither Freshwater plants or Saltwater Plants can survive. The only real option for live plants in Brackish at this sg is, to find a Brackish area and collect some plants. This does however increase the risk of bringing things into your aquarium that you do not want. IE pollution parasites and things like that!

Now about the Monos...
IMO They should be in a bigger group. ( at least 6 ) However, you aquarium is definately not big enough! Do you have other Hiding Spots for them? Is there stuff in the tank to break up sight lines so the fish can hide across the tank? I have some flat rock, and I stack it up and space it out big enough to give them a few tall, narrow areas where the Monos can take a rest from all of the activity. Do remember though that they need swimming room so dont over do it! You will always have 1 mono in the group that will grow bigger and be dominant. It's nature. Is the other fish showing signs of stress? Is it getting hurt by the picking, or is it just the other fish showing his dominance? IMO as long as it is not showing signs of stress (usually turning black/dark with monos) and it is not physically injured, I believe this to be the normal Mono pecking order!

The Substrate...
I would look around, you can find black marine sand in many pet stores. It sounds like it would give you both buffering, and the look you want..??

Lastly...The tank size.
These fish that you have, exception mollies, grow large, extremely large. But, I am not going to harrass you about what you already know. Just give some advice. For the time being, I would raise your sg to 1.012 and put a protein skimmer to work. Also Make sure your filtration is great. The more fish, the more filtration. Avg I would say is to turn over the tank 10x per hour. Being overstocked I would try to increse that, add a HOB filter. Also make sure you have a good test kit and test often!!! Do 25% water changes at least weekly, and more if necessary. I have a 75 gallon that will be overstocked soon as well, but I understand the requirements for my fish as adults, and am prepared to upgrade to a larger tank at any time, I have great filtration, use a protein skimmer and bi-weekly 25% water changes and my water stays great. 0, 0, and 30-40
Scott

[jables]

I recently concidered growing mangroves out of the back of my aquarium as they typically grown in brackish streams from what i read. my LFS can easily order them for me. im not sure about you but i live in northern Ontario Canada so if i can get them im guessing you can too

[Pufferpunk]

You'd need at least a 300g tank for a school of 6 adult monos.

[brackeeper75]

You'd need at least a 300g tank for a school of 6 adult monos.

I still disagree with this! I think 300 is way overkill for 6 6-8 inch fish. Sure in the wild they can grow to 10-12 inches, but I just haven't come across that in captivity. I would love to be proven wrong but can find no documented proof that they grow full size (beyond 6-8 inches) in captivity even with plenty of tank space. I would personally say no less than 125, ideally around 180!

[Ajordan]

I think size is only one thing to consider... activity level is also pretty important to me. If you have a fish that doesn't swim much like Hoplias malabaricus you can 'get away' with a smaller tank.

I think a 180 seems pretty reasonable from a health standpoint but it may be a little cramped given the monos love to swim. Then there are the tank dimensions to consider...

[Pufferpunk]

There is absolutely no reason a fish in captivity should not grow as large, if not larger than their wild brothers in nature, given the proper food & housing. Have you ever seen a school in a tank that large?

[brackeeper75]

I've seen them in tanks and aquarium displays much larger, and the fish were full grown and not that large(8 inches and under). I challenge you to find me documented proof. Find me pictures of Monos in a 300 gallon tank that are more than 8 inches.... I will not argue this, just prove me wrong....

I don't deny you are the King/Queen of puffers, but I have been studying and keeping Monos for many (7+) years, and I respectfully disagree with you on this.

As per the book "Brackish Water Fishes" Written by Neale Monks It says and I quote " (around 6" or 15 cm is not uncommon) An Ideal Aquarium would be 48" long and 24" deep This leaves a bit of room for some other comparably sized community fish such as a couple of scats or shark catfish." Which if you go to an aquarium calculator is (drumroll) 125 gallons.!!!

[Pufferpunk]

I guess I'll just stick with my puffers then...

[vampie]

I've never seen a full-grown mono in captivity either, though I always feel the possibility of it should be open.

It's quite a shame that trade doesn't include smaller brackish fish.

[brackeeper75]

I guess I'll just stick with my puffers then...

No disrespect meant pufferpunk!!!!!!
I think you are great and give great advice!!!
I just disagree with you on this one thing!!!
And, I am not saying you are right or wrong, just that I disagree. I challenge people to prove me wrong in this! But, no one has been able to do this as of yet.

Scott

[Rannoch]

LOL I see i've started an argument over tank sizes.

Thanks for the advice. I do plan on raising the salinity slowly.

Some Parameters of my Tank:
PH: ~7.7
Nitrite: <0.3 mg/L
Ammonia: (I think its around 0.25-0.50).
This has become a concern for me. I have started doing two water changes a week now. Normally I only do one. I think the spike in ammonia could be from the dying java ferns which i removed. I'm thinking of looking for a new test kit as well, cause the saltwater and freshwater charts colours are significantly different. IE) freshwater 0 ammonia is yellow where as the salt is brown which makes it rather annoying to read.

The only fish that i'm still concerned with is the monos. I've read in various places that the colour of them can tell you how healthy they are. However their colour tends to confuse me. All three of them are bright silver around their head and front portion of their body. They are also pretty silver at the top, but the bottom portion and the rear fin area tends to be a darker. However they tend to be darker and ligher at different times of the day. Mid-day they are really silver but and night/early morning they tend to get darker.

The darkest fish is also the "alpha" fish that chases the others around.
Any ideas what this means or am I just going crazy.

[brackeeper75]

Their color changing can mean many different things. At night they get dark to help them blend in and hide themeselves while they sleep. Stress or unhappiness can also make them change color. Their bodies should be a shiny silver. Mine do not like me invading thier space...When I am doing a waterchange or cleaning the side of the glass they all turn really dark and hide!! At night when I just have the moonlights on they are really dark as well, but when the light is on they are always shiny silver. So, Take a good look at your water. Your alpha might be dark because he is starting to get crowded. These fish need constants as they are skittish fish. I would put thier light on a timer so that is a constant. Once everything becomes constant, these fish relax and don't get so stressed out. When I walk in the door home from work they now know exactly when I get home, and are all already in the corner of the tank that i feed from waiting for me to come feed them. I can put my finger on the glass and they don't startle. These are great fish, but you gotta get them settled. They will relax with time. Aslo understand that in order for them to truly feel comfortable, you should have a school of at least 6, and I would plan on doing this soon before they get too big!! I know you are planning a new tank, but the sooner the better. Also to aid with water quality, I stand by strongly that you at a sg over 1.012 with big messy fish you should be using a protein skimmer!!! In the end if they are changing colors, it must be because of something that is spooking them. Whater quality usually doesn't change from good to bad many times over the day. And if they are bright and shiny most of the day except morning and night then it could be just normal day vs night colors for them. The light could also be spooking them...remember they are mostly wild caught and are not used to rapid changes in light. The sun just doesn't come on it is a gradual thing.I would not turn the light on and off mor than 1x a day. Turn it on let it stay on for 10 hours then turn it off. I would try to arrange this around your schedule. Mine is on full from noon to 10 and then half from 11:30 to 12 and again half from 10-10:30 and the moon lights are on the rest of the time, i think they are important, it gives the fish just enough light to see at night and makes them feel more secure.

What are you feeding them?

With a brackish tank you should be using a saltwater ammonia test!

[Rannoch]

Currently I feed them the following:

Flake Food, Freeze Dried Blood Worms, and Frozen Brine Shrimp.

I feed flake food daily, and usually freeze dried blood worms.
I feed the brine shrimp every few days.

The only other food that goes into the tank is some sinking shrimp pellets but they don't touch those.

[brackeeper75]

I vary mine's diet...
day 1 frozen raw shrimp from walmart cut into pieces and a leaf of lettuce
day 2 freeze dried krill, flake, and blood worms
day 3 frozen raw scallops from walmart cut into pieces and a leaf of lettuce
day 4 freeze dried krill, flake, and blood worms
day 5 frozen raw shrimp from walmart cut into pieces and a leaf of lettuce
day 6 freeze dried krill, flake, and blood worms
day 7 frozen raw scallops from walmart cut into pieces and a leaf of lettuce
and so on and so forth...
occasionally I throw in a couple of feeder guppies when I have them
they really like the variety It keeps them very happy

[brakishlance]

I think the suggestion about plastic plants may be the solution to more than one of your problems. I was having a similar problem with mine. I only have three, not a real school per se, but I was getting kind of concerned about the aggression one of mine was showing mainly to the other monos. I had tons of plants in my tank, but most of them came from 2 smaller 30 gallon tanks that I had. When I finally got a few correct sized plants, (ie. ones that actually went past half the height of my tank and above), it was like flipping a switch. It not only stopped the aggression, but suddenly, all three of my monos actually started acting like a school instead of three fish guarding three different sections of the tank. Now I seriously get to enjoy watching the three of them swim around my tank like I shiny row of arrowheads practicing follow the leader. I hope this helps, and good luck!

[brackeeper75]

Mine are the same way. They all school and hang out until its feeding time. Then they get a little nippy with each other. Shortly there after they settle down and get back to their school.