Before & After

[marchmaxima]

I'm struggling to get hold of any potassium nitrate so I can dose nitrates. It's hard to acquire here, having been designated a dangerous item and if you're an individual, its a bit difficult to get your hands on. Not illegal... just harder than it should be.

Aside from buying Seachem Nitrogen, anyone know of another safe product that will increase nitrates?

Or is there any other alternatives I can try? I took out the substrate again and boiled it tonight. Again it's hard to get all the cyano out of the tank this way.

Any other ideas gratefully received.

 

[Purrbox]

Try checking out the Stump Killers. Some of them are made of pure KNO3. The other place to check, would be to see if you have any hydroponic stores nearby. They should be able to get you set up with what you need.

 

[marchmaxima]

I found some KNO3! A guy I know knows a guy who knows a chemist. Messages have been passed and arrangements made for a pickup from a house I've never been to from some guy I've never met.

With the nature of these arrangements, you'd think I was picking up an illegal substance! hahahahaha. Certainly feels like it.

 

[marchmaxima]

Yesterday, i picked up a 1kg bag of KNO3 and I also picked up some KH2PO4.

I figure since I have Green Spot Algae issue and and very little Phosphates (1ppm on ast check) it is likely I need to up these level too.

So I now can un-bottom-out my Nitrates using KNO3 - dose 10ppm every water change

Q1: I assume that "dose 10ppm" means to use the calculator and dose 10ppm (which for me is around 1mg of powder). And that this statement does NOT mean that to aim for a 10ppm test reading after dosing.

I now can un-bottom-out my Phosphate using KH2PO4 and (hopefully) get rid of my green spot algae. My tap water is at 0ppm. Tank water is at 1ppm.

Q2: How much should I dose and what Phosphate test reading is within acceptable boundaries?

Q3: Assuming this doesn't work (or I get a new algae to deal with that requires ANOTHER nutrient), would it be a silly to simply think about changing to EI on this tank? Are there inherit issues doing EI dosing on a small low-light planted tank?

Sorry for all the questions.... It's the first time I've gone to dosing macro-nutrients and I'm just a little nervous about mucking it up and causing myself further problems. Not to mention that one of these substances is classified as a dangerous explosive and here I am preparing to pour it into my tank....

 

[Purrbox]

A1: Correct. If you are dosing 10ppm, you want to dose enough to raise your level 10ppm. So if it was 5ppm before dosing, it should be 15ppm after dosing.
A2: Generally you want to aim for a 10:1 ratio of Nitrate to Phosphate. It's a great starting place, but you may find that you need more Phosphate, so 5:1 may end up being more appropriate.
A3: EI would work fine on the aquarium, you'd just dose less often (perhaps once or twice a week) than with a high light aquarium.

 

[An t-iasg]

I use EI on my planted 10 gallon tank. When it was a medium light tank, I dosed three times a week. Now that it's low light, I dose the same amounts but only twice a week. It's worked out fine - I have healthy plants and no algae problems.

 

[marchmaxima]

Alright. Well, I'll start off using Joy's suggestion. We'll see how we go. If that doesn't seem to work I think I will just swap to full EI. Seems I'm half way there anyway.

I'll dose 10ppm Nitrate and 10:1 ratio of Nitrate to Phosphate each time i do a water change, which at present, is weekly. I will dose the new water so as to bring the levels up slowly and not dose based on tank volume. I am aiming to bring my tank up to 20-30ppm nitrates.

I will give it 3-4 weeks and reassess.

Someone tell me if I'm way off. Also, how many ppm of Phosphates is the safe upper limit?

 

[Purrbox]

Also, how many ppm of Phosphates is the safe upper limit?

Sounds like a good plan. I'm not aware of a safe upper limit on Phosphates. As long as you stick relative close to the ratio you shouldn't have any problems with it.

 

[HiJaC]

Sounds like a good plan. I'm not aware of a safe upper limit on Phosphates. As long as you stick relative close to the ratio you shouldn't have any problems with it.

After my phosphate dosing investigation a month or so ago i actually got mailed my tap water contents for the last two years by the water board.

It averaged 5 ppm in the tap but was up to 9 ppm last month!!

Make's me happy to know i was right in not dosing it and assure's me that plants and fish have no negative side effects at very silly levels of phosphates in the water.

Best Regards,

John

 

[marchmaxima]

Thanks for that info John.... I'll be certain now to test my tap water for Phosphates on a regular basis.

 

[HiJaC]

Thanks for that info John.... I'll be certain now to test my tap water for Phosphates on a regular basis.

As a general tip for planted tanks id say knowing your standard tap water param's was up there in my top ten. A simple e-mail conversation with the right person can be so enlightening. Especially when all the test kits in my LFS are exceedingly innaccurate.

The phosphate in my tap water (Scottish Water - Edinburgh - UK) is added by the water board to counteract the corrosion of old lead pipes in the Edinburgh area. This is more of a problem in Edinburgh then other cities in the UK as the city if full of very old buildings and pipeworks. This may not be the case where you are from.

The high levels of phosphate also threw off the standard PH to CO2 calculation for amounts of CO2 in the tank. Meaning i use a point drop from the base PH of 7.2, down to 6.2, to get my desired amount of 30 ppm CO2. This is backed up by a ph monitor and a drop checker with KH4 buffer solution.

Best Regards,

John