Aquarium plants dying

Sounds familiar?

It is to me. But then I am on the receiving end but if you go onto forums you’ll see this sort of statement all the time. I often here the same reason as to why aquarium plants are dying and it’s normally due to the fact that they have algae. They’ve been told (normally by shops) they need to starve the algae. Advice like this is sooooo old school yet the message is continually advised from shop owners who in my opinion clearly don’t know what is best.

So hobbyists follow the advice given to starve their algae and totally stop the nutrients they are putting in. Algae dies back a little and plants totally disintegrate – the reason why is simply

you’ve just starved your plants to death…

My advice to anyone who is looking for advice is speak to experts, like us (and a few others) who know what is best, and not generic shops which peddle out these toxic messages. If your plants are dying you need to first work out why. First, are they actually aquatic plants? Sounds a funny thing to ask but there are still a lot of shops that sell non aquatic plants! This only adds to confusion to hobbyists who may be doing everything else right. Below are pictures of a few non aquatic plant – looks nice heh?


problem is they will last a couple of weeks then start breaking down. These plants should live in your garden or conservatory, not in your tank. So if you have a plant that looks like these (normally they come without plant labels for identification), remove them and start again.

Secondly, are your plants getting the right nutrients? I’m recommending Neutro T for non CO2 tanks and Neutro+ for CO2 infused tanks.Your plants need no other nutrients with these ferts below.

neutro t aquarium fertiliser

neutro+ aquarium fertiliser

You add these ferts daily because that’s what plants want. Just like us, they want feeding every day – not so crazy is it? Feeding weekly is nuts and just marketing spiel to make it appear that the fertilisers are more economical then they actually are.

Are you providing your plants with carbon is gas or liquid form? If not, why not? Carbon is the backbone of plant growth and without it, your plants will suffer. Try Neutro CO2

neutro CO2 aquarium fertiliser

Are you performing weekly water changes of at least 30%? Plants need clean water unless you want to grow algae and I’m guessing you don’t.

If you follow these very basic steps I guarantee that you will have success with the majority of plants. Some that you might struggle with are advanced one’s but we’ll get onto that at another time.

If you’re still having troubles, reply to this post and let’s talk πŸ™‚ Call us on 01363 774 787.

27 thoughts on “Aquarium plants dying”

  1. Hello, I’ve had a variety of plants growing in my tank for a few months. A lot of them now appear to be dying back for no apparent reason. I have a 120cm tank with two t5 54w tubes with reflectors. My nitrates were high around 60-80ppm up until around a week ago when I got them down to around 20ppm. The plants were already dying before I lowered the nitrates. Phosphates are between 1-2ppm but may be closer to 1ppm. M lights are on for 10 hours a day and I don’t add fertilisers but I do add liquid carbon. I’ve got quite a few types of algae growing in my tank which I’m guessing this isn’t helping? I am in the process of setting up a pressurised co2 system, but what’s causing them to die off when I haven’t changed anything? Thanks.

    1. Hello Dan

      The answer is right in front of you and I quote:

      I don’t add fertilisers

      basically you’re starving your plants to death so why would they be growing? You’re giving them zero nutrients.

      Liquid carbon is good – but it aint nutrition – it’s carbon so does a different job.

      You’ve got several types of algae growing because you’re giving your plants no energy to grow, so they’re dying and algae loves that type of environment.

      So here’s what you need to do

      Add fertilisers – preferably Neutro T – available here

      Keep adding the liquid carbon.

      Make sure you have enough plants – minimum of 70% plant mass as this helps to stabilise things.

      Reduce lighting to 7 hours per day for the next few weeks. Then max of 8 hours of lighting per day.

      Perform regular water changes with a minimum of 30% per week. If you do more, your algae will hate it and die back!

      Pressurised CO2 is great but get your own house in order first – if you can’t get it right without pressurised CO2, you sure as hell won’t with CO2.

      Make sense? πŸ™‚

      1. Hi, still a learning curve for me, just want to add I do weekly water change on my 55 gallon, have a 1250 external and 200lph power head (on for couple of hours a day). I did run power head longer and BBA took over. Amonia is the catalyst, small amounts over time and before you know it, an absolute mess. My garden centre aquatic sold me a product for plants, I told them my inhabitants and the said it’s ok, erm all my snails died. I want to retaliate I’m fuming. Trying to keep fish alive constant fighting, luckily I was transferring bigger fish to new tank,dead snails leaching from external filter. BBA everywhere. Any advice welcome, tank 2 years old. Oh and BBA loves higher water changes.

    1. Never heard that before – sounds like an old wives tale. There is so much rubbish online you have to be very careful what you read/believe.

      30% in not en extreme change. 100% might be but I’ve never even known fish to have a problem with that either.

  2. Hi Richard,
    I am starting an aquascape soon and experimenting with plants in a smaller tank at the moment. I want to ensure I have a manageable tank given I am a beginner!
    On fertilisers, you recommend having daily and not weekly ferts. I have 2 questions then:
    1- I would assume with a weekly fert that the nutrients stay in the water and are gradually consumed over a week. Plants will take so much during a day depending on light and CO2 but won’t take more and therefore plenty will remain to be used during the following days. I guess it increases the risk of algae but won’t be ineffective won’t it?
    2- If you use daily dosage it is a big commitment…How do you do if your are traveling for a few days, or go on holiday for a week or two?

    1. Hi Geraud

      1) Having fertilisers just hanging around in a tank until they are used up is always a problem. It’s a bit like having your weeks shopping sat on your kitchen table until you’re ready to eat it. The alternative is to put it in the fridge and only eat what you need when you need it. Same goes for ferts.

      2) Is daily dosage really a big commitment? Is brushing your teeth a big commitment? Not really – you’ve just got to get into the habit of doing it and it’s no problem. When running a planted tank you have to commit, just like feeding your fish. Plants need looking after too.

      Yes if you go away it’s an issue (only slight though) and the odd day here and there won’t matter if you don’t dose but if you go away for a week or 2 you need to change tact altogether, but that’s an answer for another day πŸ™‚

  3. Hello Richard
    Im new to plant keeping.I got my plants last Tuesday i bean puting in easylife profio and 1m a week of nitro i have stared to see a loot of dead levies floating on top is this normal for new plant.I have a good flow in the tank all the plant are moving my lighting is not the best it is t8 aqua-glo 20w and life-glo20w my tank is 90liters this is the second time i have given growing plants ago so any help would be appreciated

    1. It happens – I wouldn’t say it was normal though. I would double your dose of profito and see how that works for you.

      Let me know how you get on in 1 week.

  4. I bought some new horizon organic peat free compost to use as substrate will this be ok for plants and fish?Alreadydone my tank tank plants don’t look to good after four days but haven’t used and nutrients you mentioned.


  5. I’ve got a 23L tropical aquarium and have started to get some plants for it. I had a floating plant which although green seems to have broken up a bit in the last couple of weeks of having it. I put in a plant from the LFS which looked healthy and happy for almost a week and then the leaves began to discolour and become translucent, then i noticed brown algae i think growing on the leaves and now it is looking very sorry for itself. I have been advised to remove the carbon filter media from my filter system and begin to add fertiliser and liquid carbon daily. I have ordered some new plants and don’t want to keep killing them off! I’m looking to have a moderately planted aquarium so that the fish have hiding places but i can still see the rocks and wood that i have in the tank. Have i been given the right advice?
    Also, I travel for work usually a day here and there which isn’t a problem i guess for fertiliser and liquid carbon but what if i’m away for a week or more?


    1. Pretty much good advice – if your plants show any signs of negative plant growth, it means they are siffering from a deficiency so you need to add more fertilisers and liquid carbon.

      Fertilisers need daily dosage so if you’re away then you’ll need to get someone else to dose or buy an auto doser.

      1. Thanks very much for confirming i’m going down the right track. Any recommendations for an auto doser for a small tank and would it be available at my LFS or would I be best to get one online?

  6. Hi there just a question about plants. I have a planted tank and I use dennerle fertilisers and dennerle co2 booster and all so dennerle food balls that goes in the gravel and I also use co2 pressurised gas can. I am feeding my plants as the instructions says but my plants still seem to be dying? I have my lights on for 7 hrs a day. Dennerle fertilise is a weekly dosage shall I split it down so I do a dosage everyday and can you tell me why my plants are dying or where I’m going wrong please and thank you.

    1. If your plants are dying then they are suffering from a nutrient deficiency.

      The recommended dose on the bottle is a guide only.

      Try trippling the dose and add daily.

  7. Hey Richard

    Recently just started a planted tank, had a year off, using the tropica soil and the powder, light is a 23w ho led 8k temp light extremely bright, my issues have been holes in leafs and brown and black leafs, tested nitrates and they’re off the scale, plants storogyne repens, hemianthus callitroids, both dieing off, dosing neutro t and your liquid carbon but both have been sitting in the shed for over a year, basically I’ve ordered an ro unit as my tap water is full of phosphates , will this resolve my problem? Along with big water changes when it arrives?
    Thanks in advance.

    1. Heh Tom

      Holes in leaves always indicates a nutrient deficiency.

      Phosphate is essential for plants so don’t use an RO unit.

      Increase your water movement with a circulation pump

      Double the amount of Neutro T on a daily basis and get some fresh stuff if yours is over a year old.

      Don’t test for nitrate – it’s a waste of time as your plants will tell you if there’s an issue.

      Hemianthus will only do well with Pressurised CO2 and A LOT of it.

      Keep trying, keep experimenting and you will succeed.

  8. Hi

    Started my first tank and doing a fishless cycle currently and about a week in. I bought a set of plants rocks and bog wood from you (50l tank) planted the plants in pool filter sand, filled with water and decor and was really happy with the result.

    Over the next few days my plants looked like they were struggling but thought they just needed time to establish. Now 1 week in and they’re worse…they’re definitely dying. Leaves are all going brown. I’ve been fertilising daily with TNC Lite. Have ordered some root plugs so will add those near to plant roots tomorrow. I’ve also dropped the temp to 25 degrees in case the 28 I was running at was too warm.

    Any thing else I can do to stop them dying????

  9. Hi

    I have just finish my new 10g tank. I have another one with 60g which have no issue. And still under cycle. The second tank I used the old plants but I notice they are dying in new tank. The light I about medium to strong

    I don’t know about the ammonia level or nitrate or nitrate bit I do Chang e water weekly around 50%

    Please help why plant are dying is it coz they were moved from old tank

  10. Is it possible to over dose Neutro T and Neutro CO2 and if so what are the signs to be looking out for?

  11. Hi Richard,

    I need some desperate help with my tanks. i am injecting co2 giving around 10 hours of ligjt and providing macro + micro nutrients and potassium as well..
    my plants are still dying and algae is growing wildly.

    m using montecarlo as carpet, alternanthera reinicki, cryptocorine wendtii as background plants.

    the seem to be going brown and algae seems to be growing on stem plants.

    kindly help me. also lemme know if u r available on whatsapp so i can video call and show u condition of my plants.


  12. Hi I need help! I bought 2 different plants the Ludwigia and sword about three days later they were brown almost just stems. I went back told fish people and he said I could try feeding them 20th they black Rock like food and I put a florescent light, now they’re barley hanging on but it doesn’t look like they’re going to make it. Please help!

  13. Hello, i used a cabomba plant for my lab. One i put in the dark and another under white light, the one in the dark stayed alive at pH of 8.5 while the one under white light died at pH of 9. Why is that?

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