Phosphate high?

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Delapool

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Picked up a phosphate test kit and got a reading of 3 to 4ppm. Not sure if this is good or bad??

Nitrates were 10 to 20ppm (sweating that test!) and ph is 7.4 in a planted tank. There is green spot algae on one plant that gets some natural light. Beard algae generally I have to spot treat every 6 months off the ornaments. I also dose liquid carbon and seachem flourish. Lights are medium lighting I think.

The phosphate a week ago was more like 5ppm. This was just after adding substrate ferts so not sure if that added to it. Since then also added more plants.

I want to try do it yourself substrate tabs but not sure on this phospate reading if it is ok or bad. If bad I was going to search for low phosphate ferts.
 
Just lurking... I've been curious about "good" phosphate readings as well.

Maybe this should be in the "Planted" section?


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Could be ;)

I wanted to check as a water quality question in general and then after that for selecting ferts. As I have plants there it would tie in - I wasn't quite sure where best to post.
 
That phosphate level is fine and not unexpected in a planted tank. What lights are you running over your tank?
 
Yes - tank is 4ft by 2.5ft tall with a Perspex cover so these give a bit more punch. Also have a 35w led strip light at the front to even up the light as the box lights are a bit spot-lightish. Lights are on for 8hrs a day.

Carbon dosing is slightly above bottle directions. I can't remember the brand but similar to API co2 booster.

Some broad leaf plants have pin prick holes in them - still working out what this means? The shop had this problem as well with no fish/snails in tank so I assume element deficiency?

Edit - ferts are seachem flourish. Substrate are some cheap pond blocks that are low in phosphate (0.5%) and have nitrogen / potassium (can't remember amounts).
 
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Is there a low and high range of phosphate to aim for? Also wondered if phosphate causes any problems for fish?
 
Your phosphate level will likely be mare than find for your plants so long as you produce enough nitrates for them. If you're not adding nitrate and you are getting up to 10ppm you'll be okay. All the aquaponics guys don't really worry about it because it kinda comes with the nitrogen cycle.

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Pinpricks are usually a potassium deficiency. I would highly recommend switching away from the liquid ferts and going with either EI or PPS Pro dosed dry ferts. It will give you more than enough fertilizers for your aquarium.

Sadly, the pre mixed ferts are usually lacking for anything beyond low light.
 
Your phosphate level will likely be mare than find for your plants so long as you produce enough nitrates for them. If you're not adding nitrate and you are getting up to 10ppm you'll be okay. All the aquaponics guys don't really worry about it because it kinda comes with the nitrogen cycle.

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Thanks. Nitrates usually are above 20ppm. I'm mostly trying to keep them down (mainly as I really hate canister filter cleaning) so was a bit surprised they weren't higher. I have added more plants now I have these box LEDs so maybe getting a balance (plus larger pwc's).

This is the first time with a phosphate test so don't have many records yet there.

Any issues with high phosphates and fish known?
 
Pinpricks are usually a potassium deficiency. I would highly recommend switching away from the liquid ferts and going with either EI or PPS Pro dosed dry ferts. It will give you more than enough fertilizers for your aquarium.



Sadly, the pre mixed ferts are usually lacking for anything beyond low light.


Many thanks - I'll chase this up. I have some dry fert websites and will try ordering some to hopefully make it past customs here in Australia.

I do want to try the do it yourself substrate ferts as well so will have to get into the hardware store.

I have seen seachem potassium here in one lfs but pretty expensive.
 
Many thanks - I'll chase this up. I have some dry fert websites and will try ordering some to hopefully make it past customs here in Australia.

I do want to try the do it yourself substrate ferts as well so will have to get into the hardware store.

I have seen seachem potassium here in one lfs but pretty expensive.

The problem with shipping dry ferts is usually the potassium nitrate because it's potentially explosive; but you really don't need it if your fish are producing enough nitrate for your tank. It's easier to buy them without that.
 
The problem with shipping dry ferts is usually the potassium nitrate because it's potentially explosive; but you really don't need it if your fish are producing enough nitrate for your tank. It's easier to buy them without that.


It was nitrates I'm pretty sure yes that could be an issue. 9 months back they found home made bombs stored in the river so I'm thinking it might be a bit sensitive at moment :)

Do I just look for anything with potassium? Will check out website tonight. I think it was green leaf aquariums website but don't have link on me.
 
Green leaf doesn't ship outside of the USA but I believe aquariumfertilizer.com will
 
I'm using potassium carbonate as a buffer. Shops quick and is cheap on Amazon. Potassium nitrate is a key ingredient in sausage, chemical stump remover, and of course, gun powder. It can also be used to make things like smoke balls, reacted with sulfuric acid to produce nitric acid, a key ingredient in nitroglycerin. Not that I'm a chemistry buff or anything....

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I'm using potassium carbonate as a buffer. Shops quick and is cheap on Amazon. Potassium nitrate is a key ingredient in sausage, chemical stump remover, and of course, gun powder. It can also be used to make things like smoke balls, reacted with sulfuric acid to produce nitric acid, a key ingredient in nitroglycerin. Not that I'm a chemistry buff or anything....

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Er, that's some detailed info there :)

I tried searching for this with no luck. I'm tempted as that would tweak my low kh up at the same time. Do you just search for potassium carbonate?
 
Er, that's some detailed info there :)

I tried searching for this with no luck. I'm tempted as that would tweak my low kh up at the same time. Do you just search for potassium carbonate?

Potassium carbonate on Amazon. Also known as pot ash. It'll jump your pH up faster than baking soda, be careful. I NEVER add it directly to the tank because of this. I use it in my AP system mainly since the goldies like the higher pH.

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Ok thanks - I'll check out on weekend. I have been using what I think is baking soda in a product to lift kh (plus have baking soda). Do you use baking soda / potassium carbonate in a planted tank? Just wondering if they can cause any issues for fish / plants?

Mainly I just add enough baking soda to keep kh around 4 or 5 so I have assumed there would be no problems but just in case? Sometimes I wonder if it is a bad thing that I do all these water changes and then over a week add chemicals like liquid carbon, ferts and kh booster back. The fish seem fine but ???
 
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