So You’ve got your tank setup and now you think you want to have a go at breeding tropical fish? You can start with normal mid to top swimmers and live bearers and egg layers at most people do or you can have a bash at something a little more difficult.

Now breeding tropical fish can range from every simple stick males and females in a tank and leave them alone (guppies!) to incredibly complex requiring you to exactly replicate the natural biotope of the fish in question. I’ve decided to focus on some simple to middle of the range fish which you can generate a nice tidy income from, more than enough to cover the running costs of your tank typically.

I have picked one of the more common types of pleco catfish and one that is a lot easier to look after and breed than some of the others available. It can often take a while to get the tank setup and the breeding group settled but the results are very satisfying especially when you have 50+ miniature versions of the parents swimming around your tank. I have of course chosen Bristlenose Plec.

The bristlenose is very easy to look after requiring not alot more than a tank with some bog wood, good water flow and filtration. They have relatively simple demands and the most important thing during all of this is ensuring your water quality is tip top, this means regular water changes and substrate vacuuming to ensure any fish poop is dealt with in a timely manner.

Preparing the tank and water parameters

While you can keep bristlenose in pretty much any environment we obviously want to maximise their potential spawn sizes so we can maximise our potential revenue after all breeding projects like this are partly for fun/challenge but also because you want to make a little money to cover your tank running costs.

The natural waters bristlenose live in are mostly soft water which is slightly acidic so the most important thing with your new tank is the PH. If you have facilities available you can use re-mineralised RO water to give you ultrasoft water but that’s not actually that important for this species of plec as opposed to some others. The key thing here is PH. In the UK most tap water is in the 7-7.5 range and while this is perfectly fine (and they will breed in it quite happily) I found I was getting the best results using a PH of 6.5-6.8 regularly getting spawns in excess of 40+ with almost a 100% hatch rate for the eggs.

I prefer more natural means of softening the water rather than chemicals so I relied on Indian Almond (capata) leaf or in one tank I put pete moss under the gravel substrate. Now pete moss is less easy to maintain a stable level with however is more cost efficient if you’re using a large tank.

For tank size you really want at least a 3 foot long tank as you’re going to be putting 4+ rather territorial fish in there so to minimise squabbles they need room to move.

Make sure there are plenty of caves in the tank I found that 2 caves per male was a good ratio though its entirely up to you, you can put in more and then remove unused ones as you’ll soon find that the males in your breeding group will pick a favourite cave and stick to that. I prefer placing the caves where the filter exit will blow across the end of the caves and slightly into it this helps quite alot with lazy / new male issues (I’ll explain in more detail shortly). The cave entrance needs to be only just wider than the size of the male. For example my fully grown male used to always spawn in a cave no wider than 2cm! They light it tight. The caves also need to be quite long 20cm or so as they need to accommodate 2 fish.

Picking your Breeding Group

Male bristlenoses can be quite aggressive to other males and also during the trapping process with the females so to spread the aggression around a little its good to keep more females than males and only one or 2 males depending on your tank size. Now I’m working on a standard 3 foot clear seal tank which is 3x1x1. I had 2 males and 4 females.

When buying your breeding group try to pick them from different sellers/shops/sources to hopefully get different blood lines. While you can interbreed brothers and sisters and parents it will weaken the gene make up of the fish making them more susceptible to diseases and early deaths. Specific line bread traits such as long fins and albinos (albino long fins being worst of all) can even further weaken the fish and can lead to random deaths/poor spawns etc. Thats not to say don’t breed albino longfins if you really want to I did with great success but it can be alot more trying than just standard run of the mill brown bristlenose.

There is no fixed do this do that at this stage its purely up to you how you go there’s no harm in over buying a group then selling off the excess and just keeping the best / most active fish for yourself.

What next?

So now you’ve got your breeding group and you’ve got your tank all nicely setup with wood and caves and hidey holes, good filtration and flow. The fish are all in and settles what now?

Wait. Then wait some more. From experience and this will change for everyone but for me personally the breeding group took about 3 months to settle in to the tank, the males to pick the caves they wanted to use and a nice pecking order being sorted among the fish. While they’re setting in remember keep on top of your water changes and ensure your water quality is tip-top and feed them regularly on veggies so cucumber/courgette etc.

Once they’ve settled in you may notice the males developing a red patch on their heads while the females start getting chubbier around the mid section. This is especially noticeable if you went with albinos as the red stands out quite a lot. The red patch on the males head indicates that he’s ready for breeding. The chubbier females indicate they’re full of eggs. My bristlenose females seemed to be on a 2 monthly cycle of being ready to breed but it will vary. Males will jump in as soon as they’re off a previous spawn. This can cause problems of the male basically starving himself without realising it as he never really comes out long enough to feed.

To deal with this you can increase their breed frequency or decrease it. Decreasing the frequency is as simple as letting your water params drop out of whack a little and feeding mostly veggies. To encourage breeding you bring your water params back into ideal and you can condition the fish by feeding them protein heavy foods such as new era plec pellets or dried bloodworm pellets.
Another trick to encourage breeding is doing a water change. Pressure drops outside ie: change from dry to raining will cause the fish to spawn sooner rather than later as in the wild this pressure drop is associated with fresh clean water coming in. So if you wake up one morning and its started/starting to rain do a larger than normal water change with fresh water and make sure the water is cooler than the tank. This fresh cold water will have them breeding over night.

The Breeding Process

Most plecs breed by the female going into a cave and then the male trapping her inside the cave. They will remain there for anything from an hour to several days so do not be massively alarmed if one of your females vanishes for a day or so. In this time neither fish will eat but the female will lay her eggs in the bottom of the cave. Once she has spat them all out the male will release the female and go back in himself. He will go in head first and will remain there for between a week and 2 weeks. During this time he won’t eat either!
After a few days about 5 ish the male will start to back out slightly eventually he’ll come fully out and then you’ll have a tank full of wigglers some still with parts of their egg sacks on them others without any egg sack remaining.

For the first few days feed the babies on crushed flake or pellets but it won’t take long before they’ll happily eat cucumber like the parents. Be careful not to overfeed protein heavy foods during this time as it will kill the babies. If there’s only bristlenose in the tank then you can quite happily leave the babies in the tank to grow up they’ll be ready for sale at about 3cm in length 🙂 If there’s other fish in there or if you’re using a smaller tank you may want to move the babies into a tank of their own to grow up to minimise the risk of them being eaten, also remember breeding is a cycle so with multiple males its perfectly possible to have one drop then another one a couple of weeks later and before you realise it you have 100+ babies in the tank and you can’t keep on top of your water quality.

Selling the young

You can sell them to your LFS most places will take them, you can sell them on ebay (I’d recommend collection only as postage is difficult) or you can sell them on fish specific classifieds such as Aquarist Classifieds.

Thats it they’re pretty simple and pretty uninvolved as long as you keep on top of your basic husbandry. There are plenty of tips and tricks you can perform but for the most part these look after themselves as long as you provide them a good environment. More complex than guppies and much more rewarding but also a good lead in to the more complex plec species should you wish and you can turn a nice bit of money to cover your running costs!

Have fun and good luck breeding your fish.