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2.5ppm PO4 in tap water

Tomasz

New Member
Joined
4 Dec 2015
Messages
14
Location
Ilfracombe
I have started 182l high tech planted tank on Tropica Soil. Dealing recently with a cloudy water (probably bacteria bloom rather than algae bloom) I have tested water parameters in my tank as well as tap water that I use for weekly water 30-50% water change.

I found that my tap water parameters exactly as reported by South West Water, i.e.
dKH 2, GH 3, NO3 5ppm, PO4 ~2.6ppm, pH 7.5

Parameters in my tank however are:
dKH 2, GH3, NO3 0ppm, PO4 0ppm, pH 6.1

I use Tropica Premium fertiliser which doesn't include Nitrogen and Phosphorus as they are in my tap water.

I understand that Tropica Soil absorbs all PO4 and NO3 from my aquarium water as it is new, however someone told me that over time it will saturate with phosphates and my tap water containing 2.5ppm of PO4 would trigger massive algae growth.

Is there anything that I could do to prevent this to happen?
 
however someone told me that over time it will saturate with phosphates and my tap water containing 2.5ppm of PO4 would trigger massive algae growth.

Is there anything that I could do to prevent this to happen?
Hiya @Tomasz

The best advice I can give you is ignore the person that's telling you these levels of PO4 will cause massive algae blooms. My tap water contains an average of 1ppm and I actively add another 3ppm of Po4 per week, lots of other people also add similar or even greater levels of Po4 and don't suffer from insane amounts of algal growth.

In general algae thrives when there's poor plant health, insufficient nutrients, to much light, insufficient CO2, insufficient 02, lack of flow, poor maintenance in the aquarium, dirty filters and insufficient water changes, more often than not its a combination of the above.

Cheers.
 
Should I introduce nitrogen fertilizer to increase the ration of NO3 to PO4?
 
Hi all,
Welcome to UKAPS.

A full tank shot of your aquarium would be very useful, as it will allow members to <"assess plant growth"> (and potentially <"plant health">).

I see you live in Ilfracombe, <"would rain water be an option for you">? I use it and you should get a lot of very clean rain, just because of where you live.
I found that my tap water parameters exactly as reported by South West Water, i.e.
dKH 2, GH 3, NO3 5ppm, PO4 ~2.6ppm, pH 7.5

Parameters in my tank however are:
dKH 2, GH3, NO3 0ppm, PO4 0ppm, pH 6.1
The phosphate (PO4---) is added to control plumbosolvency via <"Phosphate Induced Metal Stabilisation (PIMS)">, they also add some sodium hydroxide (NaOH) to raise the pH of your naturally soft water. Sodium hydroxide doesn't add any dKH (or buffering), it is <"a strong base"> so the pH can rapidly fall if you have <"any source of acids">, like <"microbial nitrification">, Indian Almond (Terminalia catappa) leaves etc.

I would recommend just ignoring pH, it isn't a very useful parameter in soft water and will <"naturally go up and down"> as your plants photosynthesise.
I use Tropica Premium fertiliser which doesn't include Nitrogen and Phosphorus as they are in my tap water.
My tap water contains an average of 1ppm and I actively add another 3ppm of Po4 per week, lots of other people also add similar or even greater levels of Po4 and don't suffer from insane amounts of algal growth.
I tend to agree with @John q . There isn't a lot of nitrate (NO3-) in your tap water, personally I would swap to the <"Tropica Premium"> for "Tropica Specialised" or cheaper option. I'm using <"Solufeed 2 : 1 : 4"> at the moment.

Adding CO2 only improves plant growth if none of the other <"essential plant nutrients"> are limiting growth.

cheers Darrel
 
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Hi, thanks. I do collect rainwater in 80l water butt for watering garden plants, however I'm not sure whether it is clear enough to be used for aquarium.
I've got both Tropica ferts - Premium and Specialised. As Specialised contains P I'm going to stop using it. I think I will stay with Premium for now and will introduce additional NO3. Would you recommend some fertilizer containing Nitro only?

Some photographs of my tank today with UV lamp working 2nd day to fight with bacterial bloom.

IMG_2677.JPG
IMG_2699.jpeg
IMG_2700.jpeg
 
Hi all,
however I'm not sure whether it is clear enough to be used for aquarium.
Some-people filter <"their rain-water">, personally I don't think <"it is a risk factor"> and am happy to use it as is.
Some photographs of my tank today
Plant growth looks pretty good.
I think I will stay with Premium for now and will introduce additional NO3. Would you recommend some fertilizer containing Nitro only?
It is difficult to only add nitrogen (N). The two options are ammonium nitrate (NH4NO3) and urea (CO(NH2)2), I really don't recommend NH4NO3 and <"with urea it will be converted to ammonia">, it just depends on the <"rate of conversion">.

People normally use potassium nitrate (KNO3), mainly because both potassium (K+) and nitrate (NO3-) are macronutrients.
As Specialised contains P I'm going to stop using it.
Entirely <"up to you">.

cheers Darrel
 
Tank looks lovely @Tomasz

The simplest way of adding NO3 would be to use potassium nitrate (KNO3), I've no idea how much premium you add but suspect the amount of potassium it adds is minimal. Adding 10ppm of no3 via potassium nitrate would also add 6.37 k, which I think in the long term would benefit the plants.

Obviously looking at the tank you are doing something right, and yes there are beautiful tanks that tick along with low nitrate levels, I'm just not sure how this will work with low nitrogen and potassium in comparison to the levels of Po4 you have in the tap water.
 
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Thank you John! I wanted to drive this tank using lean dosing, keeping N low as it stimulates colour of red plants.
It looks that my tap water with high PO4 levels won't allow me to do that. At the moment I think Tropica Soil helps me absorbing nutrients from the water, however it has limited capacity.
I was thinking about RO filter but it seems to be bit weird to filter water with almost ideal parameters just to remove phosphorus.
Also it is too slow to produce 50-70l of water.
 
It’ll clear up and be crystal clear within 24 hours of going in, in my experience.
Hmm.. No problems with slime which builds up on the inner walls of the butt?
How about warmer days? Doesn't the water smell badly?
 
Thank you John! I wanted to drive this tank using lean dosing, keeping N low as it stimulates colour of red plants.
It looks that my tap water with high PO4 levels won't allow me to do that. At the moment I think Tropica Soil helps me absorbing nutrients from the water, however it has limited capacity.

I'd say if you want to go full bore lean with your tank to promote those reds... - which btw looks absolutely awesome and I personally wouldn't change anything - you will have to go 100% RO and dose everything in excruciatingly small amounts in proper ratios.

I was thinking about RO filter but it seems to be bit weird to filter water with almost ideal parameters just to remove phosphorus.
It would be the only way to get rid of the phosphates, nitrates etc from your tap... Also, it would take seasonal variations etc. out of the equations.

Also it is too slow to produce 50-70l of water.
about 5 hours.... with a $75 100 GPD RO system.

Again, I just don't see a reason for it with how things are going in your tank unless you really, really want to for that extra control and boosting those reds.

Also, 2.5 ppm of PO4 "only" amounts to 0.83 ppm of Phosphorus. If you want to tweak the NP ratio just do what @John q suggests above.


Cheers,
Michael
 
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You can put ADA Bacter 100 in the water see how that clears up pretty good...
Jocking, don't ever do that. Look at my journal and you'll understand.

FYI and for what it's worth I dose 4.5ppm of PO4 in my tank. With accumulation it is higher than that so you don't need to worry about 2.5 ppm of PO4 levels in your tap.
 
I wanted to drive this tank using lean dosing, keeping N low as it stimulates colour of red plants.
It looks that my tap water with high PO4 levels won't allow me to do that. At the moment I think Tropica Soil helps me absorbing nutrients from the water, however it has limited capacity.
I was thinking about RO filter but it seems to be bit weird to filter water with almost ideal parameters just to remove phosphorus.
Also it is too slow to produce 50-70l of water.
what you could do is make a Nitrogen Fertilizer made from Urea and KNO3 Combination, it insure lean dosing while providing the plant with enough Nitrogen. you can skip on adding adding additional P if your tap water already have enough. your tap water looks good to me, PH from the tap is bit high but it will be countered by the acidic soil which gives you that lower PH that you currently have.

Edit: it would be wise to stay on Tropica Premium for Fe/Micros and dose N from Urea+KNO3 Combo and totally skip on P. Or, if you want to dose like Tropica, you can get NH4NO3 and K2SO4 for your N and K.
 
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Many thanks guys for your replies. I will start rising NO3 by about 10ppm and see what happens. I'm only not sure whether Potassium from Tropica Premium will be enough.
Probably because this tank is only 2.5 months old, the active soil helps me absorbing all Phosphorus from the water (NO3 as well) but sooner or later it will saturate.
 
I've ordered Seachem Fluorish Nitrogen (which contains 1.5% of N from Urea and KNO3 and also 2% of K2O) from Amazon and done some maths. I found that with weekly changes of 40l water in my tank which contains about 140l of water and dosing 10mg of Tropica Premium and 20mg of Fluorish Nitro I should get following concentrations:

N - 2.48ppm
P - 0.23 ppm
K - 2.93 ppm

Seems to be looking not too bad.
 
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