Stocking My Tank

[markandhisfish]

my tank is 3 foot by 18 inches by 12 inches what would be the maximum amount of fish i could stock it with,

 

[rabbut]

You have 120l of water there, or 25 gallons. Following the "inch per gallon rule," that allows for 25 inches of fish after your fishless cycle, and the tank is able to drop 5ppm of ammonia to zero ammonia and nitrite in 12 hours.

Lets say you want Neon Tetra sizes fish. They are about 1.25 inches long when adult (you base the 1 inch per gallon on adult length) and you have the stated above 25 inches maximum stocking level. That would equate to 20 such fish. You can put more in when the tank has matured (after 6 months) and after you have some more experience. I wouldn't put more than 30 in once the tank is fully going. Remember the latter number is reliant on the tank being mature

It is important to get the tank fishless cycled using ammonia before you add any fish Leaving the tank to sit is not fishless cycling, though you fish shop may have told you it is. If they did tell you that leaving the tank sat was fishless cycling, they lied Bacteria in the bottle products don't realy work, so if they have had you buy any of this, unfortuantely you wasted your money The only way to speed a fish-less cycle is to add some mature media, from an established tank. There is a pinned thread at the top of this board, where you can ask members for some. Some members will give their media to you for free, others will ask for replacement media or cash for replacement media. This is at their discression

HTH, and to TFF
Rabbut

 

[markandhisfish]

my tank has been up and running for about 2 months i currently have 8 neons 6 rosacious tetras a red tailed black shark ( a gorgeous specemin with strong vivid colour) a pleco a pair of pearl gourami a pair of plattys and 2 cory catfish. my water is tested weekly both by myself and my fish shop ph is 7.4 and nitrites are zero. i got the tank from a friend of my girlfriend who had it running for 4 years with a pair of oscars, he decided to sell the oscars to a fish shop and sold me the tank,heater,filter,cabinet spare power head and net etc for £150 . would i be right in thinking that as the filter had been running for all that time it would already have mature media in it? the filter was cleaned but not in the aquarium water i know this will reduce the bacteria but would any of survived?? i use a tetratest 5 in 1 kit and my fish shop uses a digital probe.

 

[geer head]

my tank has been up and running for about 2 months i currently have 8 neons 6 rosacious tetras a red tailed black shark ( a gorgeous specemin with strong vivid colour) a pleco a pair of pearl gourami a pair of plattys and 2 cory catfish. my water is tested weekly both by myself and my fish shop ph is 7.4 and nitrites are zero. i got the tank from a friend of my girlfriend who had it running for 4 years with a pair of oscars, he decided to sell the oscars to a fish shop and sold me the tank,heater,filter,cabinet spare power head and net etc for £150 . would i be right in thinking that as the filter had been running for all that time it would already have mature media in it? the filter was cleaned but not in the aquarium water i know this will reduce the bacteria but would any of survived?? i use a tetratest 5 in 1 kit and my fish shop uses a digital probe.

If you have had it set up with that many fish in it for at least a month, your filter should have enough bacteria to keep your water fine. If you want to add fish, I wouldn't take any chance though. You can add fish, but slowly (a few every week or two) and monitor it for any changes in ammonia. Also, keep in mind that a mature filter will have a certain amount of bacteria which can handle only so much nitrites, ammonia, etc. No matter how mature, adding a large load (i.e. fish) into your tank can 'overpower' your bacteria and cause an ammonia spike.

 

[markandhisfish]

my tank has been up and running for about 2 months i currently have 8 neons 6 rosacious tetras a red tailed black shark ( a gorgeous specemin with strong vivid colour) a pleco a pair of pearl gourami a pair of plattys and 2 cory catfish. my water is tested weekly both by myself and my fish shop ph is 7.4 and nitrites are zero. i got the tank from a friend of my girlfriend who had it running for 4 years with a pair of oscars, he decided to sell the oscars to a fish shop and sold me the tank,heater,filter,cabinet spare power head and net etc for £150 . would i be right in thinking that as the filter had been running for all that time it would already have mature media in it? the filter was cleaned but not in the aquarium water i know this will reduce the bacteria but would any of survived?? i use a tetratest 5 in 1 kit and my fish shop uses a digital probe.

If you have had it set up with that many fish in it for at least a month, your filter should have enough bacteria to keep your water fine. If you want to add fish, I wouldn't take any chance though. You can add fish, but slowly (a few every week or two) and monitor it for any changes in ammonia. Also, keep in mind that a mature filter will have a certain amount of bacteria which can handle only so much nitrites, ammonia, etc. No matter how mature, adding a large load (i.e. fish) into your tank can 'overpower' your bacteria and cause an ammonia spike.

most of the fish have been in a while but the rosacious tetras and the pearl gouramis were added today i dont plan to add any more fish for a few months yet , thought i would ask for an experienced aquarists advice as i do not want to overstock

 

[rabbut]

Keep an eye on the RTBS, as they can be very agressive when mature at 6 inches in length I usualy say 50gallons minimum for them, to give the other fish room to get out of their way You might get lucky and get a placid specimin, but placid TRBS are the rarety, not the norm.

Other thank that your current stocking looks fine to me

Tetratest 5in1 strips right? They are innaccurate like any strip test kit. Probes are most accurate when correctly calibrated, but pH probes asside, they can cost hundereds each A good compromise for us aquarists is liquid drop test kits, or tablet kits. These are most accurate. You want liquid drop tests for ammonia, nitrite, nitrate and pH.

Ammonia will be the first thing to rise if there is an issue, and it is one of the most toxic things your fish are likely to meet so you need to be able to monitor it. Next commes nitrite, slightly less toxic, but still able to kill, so again you need to monitor it It is after ammonia in the Nitrogen cycle. Nitrate is the last thing in the Nitrogen cycle, and we monitor it to ensure we are doing sufficient water changes. You should aim to keep it no more than 40ppm higher than your tap water nitrate content. pH is mainly a curiosity test, but in a pooly maintained tank it can "crash" We use the test to tell us what most experienced aquarists will already know, as confirmation of the issue

The API kit is regularly recomended on here and starts at about £15 online, for 800 tests, so it works out cheaper than strips despite being more accurate. I use the Tetratest liquid regent kit, and like it alot. It is more expencive than API, at about £40 online, and doing about 40 tests on adverage. It's the only one available to me though, hence why I don't switch

All the best
Rabbut

 

[markandhisfish]

Keep an eye on the RTBS, as they can be very agressive when mature at 6 inches in length I usualy say 50gallons minimum for them, to give the other fish room to get out of their way You might get lucky and get a placid specimin, but placid TRBS are the rarety, not the norm.

Other thank that your current stocking looks fine to me

Tetratest 5in1 strips right? They are innaccurate like any strip test kit. Probes are most accurate when correctly calibrated, but pH probes asside, they can cost hundereds each A good compromise for us aquarists is liquid drop test kits, or tablet kits. These are most accurate. You want liquid drop tests for ammonia, nitrite, nitrate and pH.

Ammonia will be the first thing to rise if there is an issue, and it is one of the most toxic things your fish are likely to meet so you need to be able to monitor it. Next commes nitrite, slightly less toxic, but still able to kill, so again you need to monitor it It is after ammonia in the Nitrogen cycle. Nitrate is the last thing in the Nitrogen cycle, and we monitor it to ensure we are doing sufficient water changes. You should aim to keep it no more than 40ppm higher than your tap water nitrate content. pH is mainly a curiosity test, but in a pooly maintained tank it can "crash" We use the test to tell us what most experienced aquarists will already know, as confirmation of the issue

The API kit is regularly recomended on here and starts at about £15 online, for 800 tests, so it works out cheaper than strips despite being more accurate. I use the Tetratest liquid regent kit, and like it alot. It is more expencive than API, at about £40 online, and doing about 40 tests on adverage. It's the only one available to me though, hence why I don't switch

All the best
Rabbut

my rtbs is no trouble at all he is still quite young roughly 2 to 2.5 inches he has taken up residence in 1 of the larger plants and the only aggression he ever shows is chasing other fish away if they get to close to "his" plant other than that when he is just out cruising round the tabk he mixes with the other fish fine. also i would love a discus but am a bit concerned that in a 120l tank with current stocking levels he would ultimately grow too big what is your opinion?

 

[fish are friends....]

If your going to go with comunity fish then i'd start with things like mollies, swordtails and platys as they are hardy and will be able to withstand any bad water quality you might have to start with.

 

[OldMan47]

I hate to be the one who has to tell you Mark but you already have an almost full tank. The tetras get you to a nominal 20 inches of fish, the pair of platies another 4 inches, the gouramis will go at least 5 inches each which takes you over 34 and I don't know which cories but they are at least 3 for 2 of them if they a pygmy variety. I have already counted up to 37 and I may have missed something. Like rabbut said you could get away with 1.25 x 30 = 37.5 in a fully mature tank but you are already there with no new additions and your tank is far from mature.
You have already been warned about the reliability of test strips. Conspicuously absent from your readings are ammonia readings. Since they are the first thing that usually goes wrong in a tank, it would be a good idea for a heavily stocked tank to get the liquid test kit for ammonia.

 

[markandhisfish]

I hate to be the one who has to tell you Mark but you already have an almost full tank. The tetras get you to a nominal 20 inches of fish, the pair of platies another 4 inches, the gouramis will go at least 5 inches each which takes you over 34 and I don't know which cories but they are at least 3 for 2 of them if they a pygmy variety. I have already counted up to 37 and I may have missed something. Like rabbut said you could get away with 1.25 x 30 = 37.5 in a fully mature tank but you are already there with no new additions and your tank is far from mature.
You have already been warned about the reliability of test strips. Conspicuously absent from your readings are ammonia readings. Since they are the first thing that usually goes wrong in a tank, it would be a good idea for a heavily stocked tank to get the liquid test kit for ammonia.

thanks for the reply but i think you missunderstand me i know i am pretty much reaching the limit wont even be thinking about adding anything for at least 4 months and even then only a couple more fish if any at all, i just think that at some point in time if could have a discus he would finish the tank off ncely and make an eye catching centre piece

 

[rabbut]

Discus don't do well in heavily stocked tanks, and they realy won't like the business of the tank as it is. At 8 inches adult length, I find it hard to belive that there is enough room in a 120l. Being a Discus keeper myself, I wonldn't put discus into anything smaller than 4 foot in length, and at least 2 foot high. They are big fish that need lots of room. I'd also wait untill your experience can be measured in years, as they are very unfrgiving of mistakes, and though I have 13 years behind me keeping fish now, I still make to odd one.
I would love to recomend some alternatives though, and would surgest something like angel fish if the 18 inches is the height They are similar-ish to discus but are far more forgiving

HTH
Rabbut

 

[markandhisfish]

Discus don't do well in heavily stocked tanks, and they realy won't like the business of the tank as it is. At 8 inches adult length, I find it hard to belive that there is enough room in a 120l. Being a Discus keeper myself, I wonldn't put discus into anything smaller than 4 foot in length, and at least 2 foot high. They are big fish that need lots of room. I'd also wait untill your experience can be measured in years, as they are very unfrgiving of mistakes, and though I have 13 years behind me keeping fish now, I still make to odd one.
I would love to recomend some alternatives though, and would surgest something like angel fish if the 18 inches is the height They are similar-ish to discus but are far more forgiving

HTH
Rabbut

thanks rabbut i am actually going to upgrade to a 4 ft tank sometime this year. had thought about angelfish but am blown away by discus think they are amazing. the origional enquiry was not for now but the future sometime i wouldnt entertain getting 1 unless the tank was perfect and i knew i could keep it propperly, was just seeking some advice from people with more experience than myself

 

[rabbut]

Well, wait untill you have a matured 6-month minimum aged tank, and get back to us They are cracking fish but do need a mature system

Discus are classed by many as "advanced" fish, though they aren't the hardest fish to keep. I belive this is because these fish don't read our text books Do lots of research untill you can recite the answer to any and every discus question asked in the New World Cichilds section of this forum, and then you have your background knowlage Now you've done this, bin the research and forget it You now need to copy an existing discus set-up. It should work. If it doesn't, tweak it on gut instinct untill it does The gut instinct should come from your research

All the best
Rabbut

 

[markandhisfish]

Well, wait untill you have a matured 6-month minimum aged tank, and get back to us They are cracking fish but do need a mature system

Discus are classed by many as "advanced" fish, though they aren't the hardest fish to keep. I belive this is because these fish don't read our text books Do lots of research untill you can recite the answer to any and every discus question asked in the New World Cichilds section of this forum, and then you have your background knowlage Now you've done this, bin the research and forget it You now need to copy an existing discus set-up. It should work. If it doesn't, tweak it on gut instinct untill it does The gut instinct should come from your research

All the best
Rabbut

the discus is deffinately a fish i will be having in the future but not in this tank , have just been looking at a nice 240l tank twice tha volume of my current tank. basicly there are so many fish i like but cant realisticly have any more in my 120l. hopefully should be able to get it round the end of the summer , even then tho i am in no rush for a discus but will def get 1 when i feel i am ready