What's appropriate water hardness for planted tanks?

[martinmin]

Using a TSD meter, my tap water's hardness is about 75ppm. In my tank, the ppm is about 120ppm. 1) Is the 75ppm good for planted aquarium?  

For the same tank, using acquariumcoop test, GH is around 75ppm, KH is around 40ppm, and pH is around: 6.4

Nitrate: 50ppm

Nitrite: 10ppm

2) If I don't add fish into the tank with plants only, do I need to change water to reduce nitrite? Does plant-only tank also need to be cycled by frequent water change? 

 

 

 

 

[Ninjoma]

On 5/14/2023 at 1:27 PM, martinmin said:

1) Is the 75ppm good for planted aquarium?  

Yes, that is around where I keep my tanks at. Certain plants may have more specific requirements, but I haven't had any issues with any of the species I've tried.

 

On 5/14/2023 at 1:27 PM, martinmin said:

2) If I don't add fish into the tank with plants only, do I need to change water to reduce nitrite? Does plant-only tank also need to be cycled by frequent water change?

No you don't need to cycle the tank or do water changes because of high nitrites for a tank that has plants only. Plants can utilize the nitrogen in nitrites, so it is basically food for them.

[martinmin]

On 5/14/2023 at 4:31 PM, Ninjoma said:

Yes, that is around where I keep my tanks at. Certain plants may have more specific requirements, but I haven't had any issues with any of the species I've tried.

 

No you don't need to cycle the tank or do water changes because of high nitrites for a tank that has plants only. Plants can utilize the nitrogen in nitrites, so it is basically food for them.

Will the nitrites reduce in a few days without changing water? I read from other sources that high level of  nitrites, nitrates and amanio can harm plants too, so plant-only tank also needs to be cycled as fish tank do.

[Ninjoma]

On 5/14/2023 at 4:51 PM, martinmin said:

Will the nitrites reduce in a few days without changing water?

Maybe. I wouldn't rely on the plants reducing the nitrites by a lot if that is your goal. 

 

On 5/14/2023 at 4:51 PM, martinmin said:

I read from other sources that high level of  nitrites, nitrates and amanio can harm plants too, so plant-only tank also needs to be cycled as fish tank do.

I don't think this is the case for moderate amounts of ammonia and nitrites. It definitely isn't the case for nitrates. I don't know whether extremely high ammonia or nitrites would hurt your plant, but I wouldn't personally worry about cycling a plant only tank. 

[Galabar]

Do you have any sort of filtration on the tank besides the plants (like a sponge filter, HOB, or cannister)?  If it's just plants, I wouldn't worry too much.  My understanding is that healthy aquarium plants can remove ammonia (their favorite, I think), nitrate, and nitrate.  If you just have plants, you'll probably end up fertilizing with nitrate (something like EasyGreen).

Also, although, I'm not an expert, that GH and KH sounds fine.

Edited May 15, 2023 by Galabar

[martinmin]

I have sponge filter. It's strange that I didn't add any fish, but nitrate and nitrite get very high, and I just did a 100% water change. If they don't hurt plants, probably shouldn't I change water? for plant only tanks, normally how often should I change water, to make plant grow well? 

[martinmin]

On 5/14/2023 at 5:14 PM, Ninjoma said:

Maybe. I wouldn't rely on the plants reducing the nitrites by a lot if that is your goal. 

 

I don't think this is the case for moderate amounts of ammonia and nitrites. It definitely isn't the case for nitrates. I don't know whether extremely high ammonia or nitrites would hurt your plant, but I wouldn't personally worry about cycling a plant only tank. 

Yesterday I did an almost 100% water change and the tank has only plants. The tank is not fully covered, about 70% covered with plants. New substrate, 3-week tank. The readings are below:

Ammonia: 1ppm

Nitrite: 1ppm

Nitrates: 30ppm

TSD hardness: 230ppm

The reason I am concerned is that plants don't grow well. The leaves of red plants look very dry, and leaves of green plants look dirty, with little black or gray spots.  Don't look healthy. No algae on the glass or plants.  Do the plants grow at all? Normally, the nitrite and ammonia should become zero. Right?   

 

 

[Ninjoma]

Could you provide some photos of your plants? There could be some algae growing on them or they could have nutrient deficiencies. 

On 5/17/2023 at 12:04 AM, martinmin said:

Normally, the nitrite and ammonia should become zero. Right?   

Yes, normally the ammonia and nitrite will become zero once there is enough beneficial bacteria in the tank/filter to convert them to nitrates. 

[martinmin]

On 5/17/2023 at 8:09 AM, Ninjoma said:

Could you provide some photos of your plants? There could be some algae growing on them or they could have nutrient deficiencies. 

Yes, normally the ammonia and nitrite will become zero once there is enough beneficial bacteria in the tank/filter to convert them to nitrates. 

Here are photos. I tested again and nitrates, nitrites and ammonia are very high.

 

[Ninjoma]

On 5/17/2023 at 1:23 PM, martinmin said:

Here are photos. I tested again and nitrates, nitrites and ammonia are very high.

 

Thanks for sharing these photos! I have some thoughts and some questions, but not sure I have any useful advice yet.
-It is interesting your ammonia and nitrite is very high even though you do not have any fish in the tank yet. Have you intentionally been adding an ammonia source to start cycling your tank? If not, do you have any ideas where the ammonia is coming from?
-What substrate are you using? I know some substrates, like ADA aquasoil, can release ammonia.
-Since your substrate is new, it is normal to have some brown diatom algae. This happens because new substrates contain silicates which brown diatoms like to eat. It will go away once the silicates are eaten. That could be some of -the spots on plants you are seeing (https://www.aquariumcoop.com/blogs/faqs/brown-diatom-algae) 
-Since your plants are new, it is normal to have some "melt back." This can happen because the plants you purchased may have come from a farm where they were grown out of water, so now that they are submerged they need to shed their old leaves and produce new leaves that are better suited to the new environment. If you are seeing some leaves turn brown, become soft and "melt" off, this may be the reason.(https://www.aquariumcoop.com/blogs/faqs/melting-or-dying-plants)
-Alternanthera requires high lighting to thrive. What light do you have? What is your lighting schedule? In my personal experience these plants are just hard to grow in general, so maybe someone else can provide better advise for growing those.
-Rotala blood red also requires high lighting to stay red.
-Are you using any fertilizers?

On 5/14/2023 at 6:40 PM, martinmin said:

I have sponge filter. It's strange that I didn't add any fish, but nitrate and nitrite get very high, and I just did a 100% water change. If they don't hurt plants, probably shouldn't I change water? for plant only tanks, normally how often should I change water, to make plant grow well? 

I'm not sure what the upper limit is for ammonia and nitrites harming plants. However, if your goal is to eventually cycle the tank, having the ammonia too high will hinder the cycling process. I would aim for 2ppm ammonia or lower and 5ppm nitrite or lower. 

In terms of how often should you be doing routine water changes in a plant only tank, I would suggest at least once per month. You want to be changing some water so that there isn't anything building up over time, that you wouldn't normally test for. If you have minerals in your tap water, it can also help replenish some minerals that are used up by your plants. 

[martinmin]

On 5/17/2023 at 8:01 PM, Ninjoma said:

Thanks for sharing these photos! I have some thoughts and some questions, but not sure I have any useful advice yet.
-It is interesting your ammonia and nitrite is very high even though you do not have any fish in the tank yet. Have you intentionally been adding an ammonia source to start cycling your tank? If not, do you have any ideas where the ammonia is coming from?

Answer: I might have added a little fish food 1 or 2 weeks ago, but only once if I indeed added. Nothing else. Other sources might be rotten leaves? 
-What substrate are you using? I know some substrates, like ADA aquasoil, can release ammonia.

Answer: I used two substrate A major part of it is ADA. So that might be the primary source of ammonia? The problem is now how to reduce ammonia, and nitrate, nitrite. Even a 100% water change will only bring down those in a few hours. The plants don't eat all of them?

-Since your substrate is new, it is normal to have some brown diatom algae. This happens because new substrates contain silicates which brown diatoms like to eat. It will go away once the silicates are eaten. That could be some of -the spots on plants you are seeing (https://www.aquariumcoop.com/blogs/faqs/brown-diatom-algae) 

Answer: It's good to know its brown algae and it's ugly and i had thought it is due to lack of nutrients. 

-Since your plants are new, it is normal to have some "melt back." This can happen because the plants you purchased may have come from a farm where they were grown out of water, so now that they are submerged they need to shed their old leaves and produce new leaves that are better suited to the new environment. If you are seeing some leaves turn brown, become soft and "melt" off, this may be the reason.(https://www.aquariumcoop.com/blogs/faqs/melting-or-dying-plants)

Answer: it will stop melt in 1-2 weeks? Because the tank has been planted for about 3 weeks.

-Alternanthera requires high lighting to thrive. What light do you have? What is your lighting schedule? In my personal experience these plants are just hard to grow in general, so maybe someone else can provide better advise for growing those.

Answer: I do 10 hours per day lighting, from 1-10pm. I have one light, 35.4W. My tank looks like 50 gallons? 
-Rotala blood red also requires high lighting to stay red.

-Are you using any fertilizers?

Answer: I tried a few times after water change, but now didn't. Due to the hight ammonia, nitrates and nitrites, I am afraid if I add liquid fertilizers, those parameters will. go up further?  But I do have co2 injection along with lighting. 

I'm not sure what the upper limit is for ammonia and nitrites harming plants. However, if your goal is to eventually cycle the tank, having the ammonia too high will hinder the cycling process. I would aim for 2ppm ammonia or lower and 5ppm nitrite or lower. 

In terms of how often should you be doing routine water changes in a plant only tank, I would suggest at least once per month. You want to be changing some water so that there isn't anything building up over time, that you wouldn't normally test for. If you have minerals in your tap water, it can also help replenish some minerals that are used up by your plants. 

Answer: I heard for new tanks, it's good to change water everyday for the first 1-2 weeks. Since the tank is big, changing water daily will cost a lot of water, which I don't like to do. But the question is, how to bring those parameters down if I don't change water daily? 

 

Edited May 18, 2023 by martinmin

[Lennie]

Have you been doing lots of water changes after setting up a soil tank? I personally do %50 every second day for 3 weeks. Probably your aquasoil is leeching. The excess nutrition may cause algae issues gradually, as new plants can't really utilize nutritions until they settle in.

Those black dots are the dust caused by aquasoil I believe. Should be easily wiped off

Some of the plants you planted on foreground grow crazy high and wide. Like Hygrophila difformis. Mine have grown around 60cm tall. It may gradually block your vision. It is mroe suitable as a background plant

Don't keep your lights on for too long until you start seeing nice plant growth in my experience. 6 hours a day for a new tank works great in my experience

[martinmin]

On 5/18/2023 at 12:47 AM, Lennie said:

Have you been doing lots of water changes after setting up a soil tank? I personally do %50 every second day for 3 weeks. Probably your aquasoil is leeching. The excess nutrition may cause algae issues gradually, as new plants can't really utilize nutritions until they settle in.

Those black dots are the dust caused by aquasoil I believe. Should be easily wiped off

Some of the plants you planted on foreground grow crazy high and wide. Like Hygrophila difformis. Mine have grown around 60cm tall. It may gradually block your vision. It is mroe suitable as a background plant

Don't keep your lights on for too long until you start seeing nice plant growth in my experience. 6 hours a day for a new tank works great in my experience

Since the tank is big, at least 50 gallons, I guess,  I have been reluctant to change water frequently. Maybe I have to change water more frequently and see how it goes.

[Lennie]

On 5/18/2023 at 10:59 AM, martinmin said:

Since the tank is big, at least 50 gallons, I guess,  I have been reluctant to change water frequently. Maybe I have to change water more frequently and see how it goes.

Aquasoil leeching in the early stage is very normal. Dont worry, just keep up with big water changes preferably very often for now.

I always use tropica aquasoil and it does leech a lot. I know ADA leeches even more! What did you use?

In a small tank, you use much less aquasoil. But in a bigger one, you use much more. So basically the same thing when you consider the substrate/water ratio. 

I feel you. Doing up to %50 water changes very often is kinda bothering. But sadly it is what it is

 

[martinmin]

If I don't plan to add fish, how can I produce beneficial bacterial? Should I add fish food to produce it? 

[Lennie]

On 5/19/2023 at 6:23 AM, martinmin said:

If I don't plan to add fish, how can I produce beneficial bacterial? Should I add fish food to produce it? 

You reading ammonia right now is already enought to start it. You can actually cycle with that ammonia if I'm not wrong. You may introduce some established media, bottled bacteria or just wait for a very long time. If you haven't dipped your plants, they must come with some beneficial bacteria on them and introduce some.

You should have a source of ammonia to start the cycle. That is the important part.

You can add fish food too, as it breaks down, ammonia comes out. But in my experience, although it cycles, it is messy and inconsistent. I would personally not cycle with fish food again.

 

Do you know anyone that is a fishkeeper that you can trust their filter media? If so it can be great. 

Otherwise, I would introduce some bottle bacteria to jump start. Or else, it takes way too long for it to establish on its own

Edited May 19, 2023 by Lennie

[martinmin]

On 5/19/2023 at 12:47 AM, Lennie said:

You reading ammonia right now is already enought to start it. You can actually cycle with that ammonia if I'm not wrong. You may introduce some established media, bottled bacteria or just wait for a very long time. If you haven't dipped your plants, they must come with some beneficial bacteria on them and introduce some.

You should have a source of ammonia to start the cycle. That is the important part.

You can add fish food too, as it breaks down, ammonia comes out. But in my experience, although it cycles, it is messy and inconsistent. I would personally not cycle with fish food again.

 

Do you know anyone that is a fishkeeper that you can trust their filter media? If so it can be great. 

Otherwise, I would introduce some bottle bacteria to jump start. Or else, it takes way too long for it to establish on its own

"Do you know anyone that is a fishkeeper that you can trust their filter media": yes, I do. You mean I can brow a filter and install it on my tank, or just take a filter media, but then how to use the filter media itself? It's unlikely we have the same filter type.

[Lennie]

On 5/19/2023 at 6:53 PM, martinmin said:

"Do you know anyone that is a fishkeeper that you can trust their filter media": yes, I do. You mean I can brow a filter and install it on my tank, or just take a filter media, but then how to use the filter media itself? It's unlikely we have the same filter type.

If you are sure that they wont transmit any disease or whatsoever to your tank, Then you can take some filter media, like some biorings, a cut of sponge etc from their filter and add it inside your HOB/filter for example.

Another option is, you can also give your filter to your friend and let them run that filter in their tank at the same time with their filter. I would personally say at least 2 weeks. This would also help with your filter to get seeded with beneficial bacteria.

 

Are you planning to use only that internal filter in that tank?

Edited May 19, 2023 by Lennie

[w0walana]

Let your tank sit. I'm assuming the tank was recently set up so the soil is just leaching. Stop doing water changes as well. You can resume water changes once ammonia and nitrite are 0 to reduce nitrates (or to clean up the tank a bit). Plants will take up ammonia and nitrite way before they do nitrate, even without light. They only take up nitrate as a last resort and only during peak photosynthesis. they have to convert the nitrate all the way back to ammonia which requires a good amount of energy (light + co2).

On 5/18/2023 at 11:23 PM, martinmin said:

If I don't plan to add fish, how can I produce beneficial bacterial? Should I add fish food to produce it? 

the beneficial bacteria grows on its own. you just need to wait. unless the soil is leaching all 3 nitrogen compounds, you already have beneficial bacteria in the tank converting ammonia to nitrite and then nitrate. how long has the tank been set up?

[martinmin]

On 5/19/2023 at 9:55 AM, w0walana said:

Let your tank sit. I'm assuming the tank was recently set up so the soil is just leaching. Stop doing water changes as well. You can resume water changes once ammonia and nitrite are 0 to reduce nitrates (or to clean up the tank a bit). Plants will take up ammonia and nitrite way before they do nitrate, even without light. They only take up nitrate as a last resort and only during peak photosynthesis. they have to convert the nitrate all the way back to ammonia which requires a good amount of energy (light + co2).

the beneficial bacteria grows on its own. you just need to wait. unless the soil is leaching all 3 nitrogen compounds, you already have beneficial bacteria in the tank converting ammonia to nitrite and then nitrate. how long has the tank been set up?

It's close to one month. I am afraid too much ammonia, nitrates and nitrites will "burn" my plants and that's why the plants look dry or black? 

[w0walana]

On 5/19/2023 at 1:01 PM, martinmin said:

It's close to one month. I am afraid too much ammonia, nitrates and nitrites will "burn" my plants and that's why the plants look dry or black? 

they won't burn your plants at all. to prepare for fish, you usually have to do daily 50% water changes for the first week, 50% water changes every other day for the second week, 50% every few days for the third week, then weekly afterwards. however, i would just do weekly water changes if you aren't in any rush. here's an article by diana walstad about nitrogen uptake as well https://dianawalstad.files.wordpress.com/2017/05/biolfiltration2017a.pdf

btw, your plants look completely fine to me! that co2 injection is also helping your plants grow a lot.

the black or dryness youre talking about is probably debris/algae you can wipe off or decaying old leaves that were grown out of water.

[nabokovfan87]

On 5/14/2023 at 1:27 PM, martinmin said:

Using a TSD meter, my tap water's hardness is about 75ppm. In my tank, the ppm is about 120ppm. 1) Is the 75ppm good for planted aquarium?  

@Seattle_Aquarist can you help guide us here?  We have a ton of great plant minds on these forums as well that would be extremely helpful too!

A small example here is my water, which is (or was) seemingly very different than yours and now is very similar to yours.

Initially...
GH: 450-550 ppm
KH: 100-150 ppm

Now I have to use buffers:
GH: 150-200 ppm
KH: 60-80 ppm

There are a few places like flowgrow.de that have a very robust plant database and they do list hardness values for a lot of plant species.  Tropica also has the information on their website, I am sure there are others.

On either set of parameters the plants were growing and doing fine.  Tank was moved, plants and CO2 crashed, I lost about 75% of the leaves on the plants due to all the issues I was having with TDS and plant damage.  After a few months I have GH>KH again with the buffers and we're back to seeing the plants growing well.  As always, be very careful using TDS as an indication of any sort of hardness in your water.  Cory has videos showing what TDS meters can be fooled by and it's a critical lesson.  As hobbyists we like things to be easy, but knowing GH/KH definitively in lieu of just TDS is important for success. Using RO water with a buffer with TDS as a metric makes sense because that is a very controlled situation.  As soon as you use tap water in place of RO+Buffers the TDS loses a lot of it's value.  You always should (a lot of people don't) default back to individual testing for GH and KH.

[martinmin]

On 5/19/2023 at 10:09 AM, w0walana said:

they won't burn your plants at all. to prepare for fish, you usually have to do daily 50% water changes for the first week, 50% water changes every other day for the second week, 50% every few days for the third week, then weekly afterwards. however, i would just do weekly water changes if you aren't in any rush. here's an article by diana walstad about nitrogen uptake as well https://dianawalstad.files.wordpress.com/2017/05/biolfiltration2017a.pdf

btw, your plants look completely fine to me! that co2 injection is also helping your plants grow a lot.

the black or dryness youre talking about is probably debris/algae you can wipe off or decaying old leaves that were grown out of water.

Since I don't plan to add fish at all for any time soon, so  I would just not change water and see how it goes. If the 3 parameters continue to remain high, does that mean no beneficial bacteria have been developed yet?  

[martinmin]

On 5/19/2023 at 10:35 AM, nabokovfan87 said:

@Seattle_Aquarist can you help guide us here?  We have a ton of great plant minds on these forums as well that would be extremely helpful too!

A small example here is my water, which is (or was) seemingly very different than yours and now is very similar to yours.

Initially...
GH: 450-550 ppm
KH: 100-150 ppm

Now I have to use buffers:
GH: 150-200 ppm
KH: 60-80 ppm

There are a few places like flowgrow.de that have a very robust plant database and they do list hardness values for a lot of plant species.  Tropica also has the information on their website, I am sure there are others.

On either set of parameters the plants were growing and doing fine.  Tank was moved, plants and CO2 crashed, I lost about 75% of the leaves on the plants due to all the issues I was having with TDS and plant damage.  After a few months I have GH>KH again with the buffers and we're back to seeing the plants growing well.  As always, be very careful using TDS as an indication of any sort of hardness in your water.  Cory has videos showing what TDS meters can be fooled by and it's a critical lesson.  As hobbyists we like things to be easy, but knowing GH/KH definitively in lieu of just TDS is important for success. Using RO water with a buffer with TDS as a metric makes sense because that is a very controlled situation.  As soon as you use tap water in place of RO+Buffers the TDS loses a lot of it's value.  You always should (a lot of people don't) default back to individual testing for GH and KH.

 

I just tested again, and those are values (based on aqc's test strip):

GH>150

KH: around 40

nitrate: 50-100

Nitrite: 10

 

The gap between GH and KH is too big? 

Edited May 19, 2023 by martinmin

[w0walana]

On 5/19/2023 at 4:26 PM, martinmin said:

Since I don't plan to add fish at all for any time soon, so  I would just not change water and see how it goes. If the 3 parameters continue to remain high, does that mean no beneficial bacteria have been developed yet?  

not necessarily, it could mean that there aren't enough bacteria colonies to handle all the nitrogen being released in the water.