I have Co2, Lights, Fertz... Still going wrong!

Hello everyone and thank you for taking your time to even read this. I'm having an issue with my plants in my tank.

I do a weekly water change of 10-20L out of a 75L tank. I am using a CO2 diffuser connected to my canister filter. I am using a daily fertilizer( PRO JBL Flora Ferropol 24) as well as a weekly (Tropica Specialised Nutrition) after my water change combined with phosphates by easy life. My lighting is a Fluval 3000-25,000K, 16 WATT LED light which I recently added. My soil is Fluval plant and shrimp stratum.

The tank is stocked with 4 ottos, 30 neons, 4 rainbows ( small, I'm cycling a 200L tank for them ), 2 platies, 2 pearl gourami ( Small, same situation as rainbows ), and 2 siamese algae eaters.

My red plants are not as colourful as it was when I originally bought it, they are also withering away. The green plants are also withering and collecting horrible algae.

I have the photos posted as a reference to everything mentioned above.

If you need any more information, let me know.

Thank you!

A picture of my tank, I removed a few plants that I believed were too far gone yesterday. I added new plants; Alternantheras reineckii mini, Nymphoides hydrophylla, Utricularia graminifolia, Rotala indica.

Don't mind the Co2 indicator, I changed the liquid last night

What is the pH, GH & KH of the water?
The rainbows need a GH above 150ppm and a pH above 7.0.
The platies need a GH around 200PPM+ and a pH above 7.0.
The other fish you listed prefer soft water with a GH below 150ppm and a pH below 7.0.

If you don't have enough KH in the water, the CO2 can cause the pH to drop rapidly and weaken or kill the fish.

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A lot of red and pink plants sold for aquariums are actually marsh plants that don't do well underwater. Alternantheras and purple waffle are two commonly sold plants that should be left in the garden and not put into an aquarium.

It looks like you have hair grass in the tank and this doesn't do well underwater. It prefers wet feet and dry leaves.

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How long is the light on for each day?

What Kelvin rating do you normally run the light at (3000-25,000K)?

Plants do best with a Kelvin rating of 6500K, with a similar amount of red and blue light with a bit of green thrown in for good measure. If the Kelvin rating is too high (10,000-25,000K), you will have different shades of blue, violet and ultra-violet light. At 3000K it is mostly red and yellow light.

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You should do bigger water changes each week. A 75-80% water change each week will dilute any remaining nutrients and give you a fresh start with the fertilisers. By doing small water changes you are potentially leaving unused nutrients behind and these will build up over time and encourage algae.

Phosphates and nitrates should not be added to tanks because they are not needed by aquatic plants and encourage algae.

Based on your pictures you are short one or more of the essential plant nutrient needed for good growth. You need to make sure your fertilizers have all of the following nutrients (nitrogen, potassium, calcium, magnesium, phosphorous (typically posphate) sulfur, chlorine (typically a chloride salt), iron, manganese, boron, zinc, copper, molybdenum, nickel. If you are missing any one of the above nutrient the plants will not grow and will eventually die. Basically your plants are struggling to get the nutrients they need to grow. So that leaves a lot of excess nutrients in the water which algae can feed on. I have found no fertilizer on the market that have all of the essential plant nutrients.. Typically they don't have calcium, magnesium, and are often short on zinc and copper. Typically tap water supplies a lot of these but not always.

Unfortunately for the fertilizers you list I have not found any ingredients list for them or any useful information on the bottle. Without knowing that I cannot tell you what is wrong. However I would check your GH. The GH test tells you how much calcium and magneism is in the water. If the number is less than 4 degrees I would probably add a GH booster to add the necessary calcium and magnesium. We also need to know your nitrate and PH levels. Iverall I think you have a mobile nutrient deficiency. Mobile nutrients are nutrients plant can remove from old leaves and move to support new growth. If the deficiency last long enough the old leaves will die and fall off. Mobile nutrients are nitrogen, potassium, phosphate, magnesium, chloride, and molybdenum. You probly don't have a potassium phosphate deficiency due to the phosphate fertilizer you are using. If your test kit shows measurable nitrates you don't have a nitrogen deficiency.

All of the plants in your pictures should grow very well once the deficiency is corrected.

I thank you both kindly for taking the time to give such helpful, long and detailed answers to my problem. I was busy with work so did not make it out to get the GH and KH tests yesterday. I got them today though

My results are

KH: 4dH.
GH: 14dH.
pH: 6.4.
Ammonia: Very small spike. ( I check this every week, never a spike. )
Nitrite: 2ppm.
Nitrate: 160ppm.

I'm also after doing a 75% water change.

As well as adding Tropica nutrition capsules. I planted three of them.

Colin_T said:

What is the pH, GH & KH of the water?
The rainbows need a GH above 150ppm and a pH above 7.0.
The platies need a GH around 200PPM+ and a pH above 7.0.
The other fish you listed prefer soft water with a GH below 150ppm and a pH below 7.0.

If you don't have enough KH in the water, the CO2 can cause the pH to drop rapidly and weaken or kill the fish.

--------
A lot of red and pink plants sold for aquariums are actually marsh plants that don't do well underwater. Alternantheras and purple waffle are two commonly sold plants that should be left in the garden and not put into an aquarium.

It looks like you have hair grass in the tank and this doesn't do well underwater. It prefers wet feet and dry leaves.

--------
How long is the light on for each day?

What Kelvin rating do you normally run the light at (3000-25,000K)?

Plants do best with a Kelvin rating of 6500K, with a similar amount of red and blue light with a bit of green thrown in for good measure. If the Kelvin rating is too high (10,000-25,000K), you will have different shades of blue, violet and ultra-violet light. At 3000K it is mostly red and yellow light.

--------
You should do bigger water changes each week. A 75-80% water change each week will dilute any remaining nutrients and give you a fresh start with the fertilisers. By doing small water changes you are potentially leaving unused nutrients behind and these will build up over time and encourage algae.

Phosphates and nitrates should not be added to tanks because they are not needed by aquatic plants and encourage algae.

Click to expand...

How can I check the Kelvin rating?

The tank is running light for 12 hours. I have the settings on the app set to pro with settings adjusted for plant growth. I only got this light last week. Before that, I was running the light that came with the tank.

The Kelvin rating is normally written on the globe and is the number with a K after it. eg: 5000K = 5000 Kelvin.

Emmet said:

KH: 4dH.
GH: 14dH.
pH: 6.4.
Ammonia: Very small spike. ( I check this every week, never a spike. )
Nitrite: 2ppm.
Nitrate: 160ppm.

Click to expand...

Could you post the same test results for the water you put in to the tank without any fertilizers added. Your nitrate is very high. You only need 5 to 10ppm of nitrate for plants to do well. At 160 your fish might not do well.

Emmet said:

As well as adding Tropica nutrition capsules. I planted three of them.

Click to expand...

I don't use root tabs because you really hove no way of knowing how fast they release the nutrients. In some thank they may dissolve slowly. In some tanks they may dissolve very fast. I am concerned you high nitrate levels might b due to the root tabs.

After the water change,

StevenF said:

Could you post the same test results for the water you put in to the tank without any fertilizers added. Your nitrate is very high. You only need 5 to 10ppm of nitrate for plants to do well. At 160 your fish might not do well.



I don't use root tabs because you really hove no way of knowing how fast they release the nutrients. In some thank they may dissolve slowly. In some tanks they may dissolve very fast. I am concerned you high nitrate levels might b due to the root tabs.

Click to expand...

I've stabilised my tank in regards to the ammonia, I believe the spike was caused by the power cutting out and the filter being off for a few hours while I was working.

My nitrate returned to 80ppm. I only added the root tabs as I believed they would fill the gap on the lack of other nutrients.

Colin_T said:

The Kelvin rating is normally written on the globe and is the number with a K after it. eg: 5000K = 5000 Kelvin.

Click to expand...

I am unsure what you mean by the term globe. I checked the light with no references to any kelvin rating on it. It does have 3000-25000K on the box if that is it?