Phosphates

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hellohefalump

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On the internet forums, I'm led to believe that phosphates are good for plants.

The manager of my LFS, who usually gives pretty sound advice, says they're bad. He also told me he used to work in a plant nursery and the only time they dosed phosphates was when they wanted plants to flower. Otherwise they just cause algae.

I measured my PO4 today, and mine are high! they are 4. Or 3, depending if I'm reading the chart right, I wasn't sure. But anyway, they're over 2 which was the highest I wanted to see.

It looks like my plants aren't using them up that quick, and my algae is getting a bit worse again.

I did a 1/3 tank water change today, with RO water in case theres phosphates in my tap (with extra kh liquid - Kent ph buffering stuff - I raised the kh to 4dkh).

So... why are phosphates good?
 
On the internet forums, I'm led to believe that phosphates are good for plants.

The manager of my LFS, who usually gives pretty sound advice, says they're bad. He also told me he used to work in a plant nursery and the only time they dosed phosphates was when they wanted plants to flower. Otherwise they just cause algae.

I measured my PO4 today, and mine are high! they are 4. Or 3, depending if I'm reading the chart right, I wasn't sure. But anyway, they're over 2 which was the highest I wanted to see.

It looks like my plants aren't using them up that quick, and my algae is getting a bit worse again.

I did a 1/3 tank water change today, with RO water in case theres phosphates in my tap (with extra kh liquid - Kent ph buffering stuff - I raised the kh to 4dkh).

So... why are phosphates good?

Phosphates are good for plants. It enables the plants to obtain the phosphorus they need in order to make up part of their structure.
Phosphates in a planted tank will not cause algae, but rather a limited supply of it will. Ofcourse if you had a tank with just water in it and plenty of phosphate, then yes you would get algae. However, in a planted tank, the plants need the phosphate in order to grow. Otherwise their structure beings to uncontrollably leach ammonia when breaking down. Algae spores will use the ammonia to reproduce and before you know it, you've got algae problems. Just look at some of the tanks on here and on other planted enthusiast sites, we use NPK and the plants grow fantastically with no algae problems. If there is algae, then we ourselves are missing something out (could be flow, CO2 or organic waste).
If a planted tank contained good nutrients and lighting, yet algae persisted, then CO2 would most likely be the limiting factor which isn't allowing the plants to absorb the nutrients.
We perform 50% water changes a week to effectively remove 50% if the ammonia and algae spores in the tank. It also gives us an idea as to how much nutrients are in the tank. The ammonia I'm talking about isn't detectable on regular testing kits. Those kits are calibrated to show "0" when the level is no longer toxic to fish. However ofcourse, the amount of ammonia in the tank is never going to be completely 0, otherwise there would be no nitrogen cycle.

If you are getting algae then some info of your tank set up could allow us to help solve the problem.

Tank size
Lighting, on for how long, recently purchased bulbs, how much wattage?
CO2, any at all, fermentation or pressurized?
Nutrients, what and when?
Water changes, how much and how often?
Whats the filtration like?
What plants do you have and how much coverage is there (%)?

Oh, btw, a phosphate reading of 2, 3 or 4 is fine. In some circumstances extremely high levels can alter KH I believe.
 
Thankyou for your quick reply! And for clarifying that PO4 IS important. I thought he was wrong... but he seemed so certain!


Tank size - 400litres/100gallons
Lighting, on for how long, recently purchased bulbs, how much wattage? - recently perchased bulbs. On for 11 hours, 4 bulbs at 54watts
CO2, any at all, fermentation or pressurized? - pressurised, 30ppm, measured with 4dkh solution. Two units, one at each end of the tank next to filter outlets. I think it's being pushed around pretty well, because all my water appears to be moving (plants sway) and I can see particles moving around the whole tank in the water.
Nutrients, what and when? - PPS pro.
Macro Solution

In 1 liter bottle:
59 grams K2SO4 (Potassium Sulfate)
65 grams KNO3 (Potassium Nitrate)
6 grams KH2PO4 (Mono Potassium Phosphate)
41 grams MgSO4 (Magnesium Sulfate)
Fill with distilled water and shake well. Let sit overnight.

Micro Solution

In 1 liter bottle:
80 grams of CSM+B or equivalent trace element mix
Fill with distilled water and shake well. Let sit overnight.


How do I dose PPS-Pro solutions?

Dose 1 ml of each solution per ten gallons of tank size. Dose prior to lights turning on.
Water changes, how much and how often? - sporadic. I'm trying for 25% a week. Although in reality it's more like 1/3 to 50% every other week.
Whats the filtration like? - Tetratec EX 1200 external filter, and standard juwel internal filter. One at each end of the tank.
What plants do you have and how much coverage is there (%)? -
Hemianthus 'cuba'
Hemianthus Micranthemoides
java fern
java fern 'windelov'
Aponegeton Madagascarieisis (lace plant)
dwarf hair grass
Hygrophila difformis
Hygrophila corymbosa 'red'
Crinium calamistratum
Nesaea Crassicaulis
vallis
crytocoryne wendtii 'tropica'
moss balls
xmas moss

Not sure about coverage, here's a pic: (note plants are a bit taller than this now they're not quite to the top, but maybe half way. Nessea crassicaulis is at the top now.)
DSCF0086.jpg

right side
DSCF0087.jpg

left side
 
Good good.
I'm not fully familiar with the PPS pro method of dosing so can't really comment. Although, if you are still getting algae then obviously I would dose more considering if everything else was up to par. However it's the water changes which might be the cause here as well. I'd say the 50% a week is very important in planted tanks. It prevents the ammonia build up which can be leached by any decaying organic matter. Cleaning part of the Juwel filter every 2 weeks will help too. Aim to clean part of the external every month or so. I invested in a 1000lph eheim pump which has enabled me to do water changes much quicker.
Everything else looks fine, your on the right lines for sure.
Photos don't look like its got 4x54W :fun:
Which type of algae did you say you were getting?
 
In answer to the fish shop owners advice......Tell him to stick to fish and forget about plants. lol. On a more serious note, many people who have been into fish for a long time have this belief as it was what most people believed. Over the past 10-15 years this has been challenged, then corrected to the point where ALL serious aquascapers, aquatic gardeners add phosphate. Not really the lfs owners fault as he tells you what he has been told and researched. I would say he hasn't checked up on latest research. Aome people even on this site and others will still argue the 'phosphate causes algae' point much to the open minded 'new school' frustrations.

PPS Pro is a very very lean dosing method. In fact it can border on the defficient limit for some nutrients. I am not a fan but I do know some people who use it and the successes are in the minority.

There is no way you should be getting phosphates as high as that on PPS Pro as it is one of the nutrients that is too low with that particular method (IMO and others.) I can only assume that either your tap water is loaded to the hilt with phosphates (I doubt it is that high) or that you feed too much to your fish. lol. The plants being defficient in another nutrient will probably be contributing to the build up.

I assume you are after a lean dosing regime that also means low water changes. Therefore I have put a link at the end of this post to a lean dosing regime that is not as limiting and 20% weekly/10% bi weekly is OK.

Your lights are quite high. Being a very large tank the WPG rule is ineffective. Larger tanks need less light to reach high light which I would say yours is. Therefore CO2 distribution is very very important. your lights also look a funny colour. They look more like beauty lights (2000K) than anything we usually use for plants. Very orange. 4-10K is much better for colouration.

As your CO2 ppm is 30 at both ends then around the filters it seems to me that you are on the ball. I would however try moving 1 DC to the back centre for 1 week and then to the front centre the week after just to check that you have 30ppm all around the tank and not just at the ends.

Filtration is the final thing I am not sure how much lph you have with the Juwels but I would guess that they in no way get up to the 10x volume that we would usually suggest for planted tanks. For a 100USG you should aim for 4000 total lph. The Tetratec is 1200. Are the Juwels 1400 each? I would guess nowhere near.

This is the link I suggested. There is a lot of info on this site and you should be able to glean lots of other interesting and helpful info from it too:

http://www.theplantedtank.co.uk/PMDD.htm

AC
 
The photos were taken when I only had two bulbs on. The one's that came with the Juwel 'hi lite' unit, so Juwel ones. I have since upgraded, added an additional two bulbs, because my plants didn't seem to be growing very quickly and my Hemianthus Micranthemoides was getting very 'leggy' and appeared to be dying. And my HC was growing upwards, not sideways. Since upgrading the lights, plant growth has been much faster and the HM is thriving.

I just had a look on the back of a Juwel light bulb packaging, and it says they're 4100 kelvin. I have two of these. I also have an arcadia freshwater plant bulb (not sure on kelvin) and a marine bulb, which I know isn't ideal but my LFS doesn't have anymore of the arcadia ones in the right size, and my ballast doesn't work unless there's two lights. I keep going in to see if they've restocked, but no luck.

I agree the Juwel ones are very orange. I'm waiting for my LFS to start stocking the new arcadia T5s that fit the Juwel ballast.

I invested in a 1000lph eheim pump which has enabled me to do water changes much quicker
How does that work? At the moment I'm using a syphon into my bath for emptying water. But then I use watering cans to replace it, which takes forever. I normally use half and half RO and tap water.

However it's the water changes which might be the cause here as well
I do notice algae gets better after a water change.

Which type of algae did you say you were getting?
I've had quite a few types, most of which are better now and I think were due to the tank settling down. At the moment the most problematic are green spot and I think a LITTLE bit of green dust. It's on the front glass. There's also a little bit of hairy stuff on some of my leaves, but hardly any and I think it might be getting better on it's own now (it's on the older leaves not the new ones).

As your CO2 ppm is 30 at both ends then around the filters it seems to me that you are on the ball. I would however try moving 1 DC to the back centre for 1 week and then to the front centre the week after just to check that you have 30ppm all around the tank and not just at the ends.
will do that.

Filtration is the final thing I am not sure how much lph you have with the Juwels but I would guess that they in no way get up to the 10x volume that we would usually suggest for planted tanks. For a 100USG you should aim for 4000 total lph. The Tetratec is 1200. Are the Juwels 1400 each? I would guess nowhere near.
is there a way I can upgrade the pump or do I need a whole new filter? I know Tetratec do a bigger filter than the one I've got, but it's a lot of money. 4000lph is a lot! I'd need just under TWO of the biggest Tetratecs! Is it the actual filtration that needs 4000lph, or is that flow? Could I add a powerhead or two?

or that you feed too much to your fish.
I do have quite a lot of fish (this used to be a fish only tank). I don't feed them every day though, more like every two or three days. I wouldn't say I over feed... but maybe I just THINK I don't? I'm pretty sure I don't though because I used to work in the LFS and part of my job was fish feeding and nobody ever commented on the amounts I was giving. They only got fed twice a week though.



I checked out the plantedtank link to the dupla drops, all the things added are the same but according to my calcs (which I aren't good at so I may be wrong) you're adding slightly more Macros, but less Micros.

I can see the point that more Macros are a good thing, but why less micros? I'm assuming the hydrochloric acid is to prevent fungus and has no fert benifit?
 
Look on the same link I posted for the ferts but on the 'on the cheap' tab and then T5 lighting. There is no need to buy 'aquarium' tubes at an inflated price. You are paying for the ink used to print the word aquarium and a fish picture on the packaging. The tubes are the same as normal tubes. It is the water tight end caps of the starter unit that is different. You will find the normal tubes are 1/3rd of the price (expensive ink on aquarium tubes. lol)

4100K is fine. As is the freshwater which will be 6500K. I would get another 6500K to replace the marine one. The 2 6500K (daylight) bulbs should then balance out the orange/pink ones. The link I posted before has pics of many different colour combos and some useful info as well.

GSA (Green Spot Algae) is caused by low phosphates which answers your initial question. lol

My main qualm with PPS Pro is that it over eggs the micros (of which plants need only a little really) and doesn't dose enough macros which are the plants main needs. Its like having a roast chicken meal with a 1cm piece of chicken and then putting ½pint of gravy on top. The 'dupla drops' with added PO4 are the reverse where they add a very slight excess of macros and micros.

Tap water has more diffused CO2 in it than tank water naturally has (without pressurised CO2) therefore your water change may be telling you something here.

We say 'filtration' but you are right, it is the circulation that is what we mean. Powerhead(s) is/are fine. My filter is 6x and I have a powerhead to make up the difference.

I don't bother with the acid. You are correct again, it is to stop fungus. I wouldn't worry about it if you don't want it.

AC
 
To use the pump I also purchased a few meters of 16/22mm tubing that attaches to the outlet on the pump. Place the pump in the tank and lead the other end of the tubing into the bath or outside. Plug the pump in to a socket and it begins to work It pumps water out effectively. I use the same technique to fill the tank up as well. One thing I've noticed, if the container is getting too full and you unplug the pump, water will still drain into the container via siphoning. In which case pull the pump out of the water when it's switched off so the siphoning stops.
 
True, but also too much if the plants cant use it, you have to find the sweet spot, this is the only algae caused by PO4 overdose.

I was talking to JamesC on UKAPS about it.
 
The tanks been set up for years so the filters are mature, but it was a low light/low light plants/no CO2 setup. It's been highly lit, and planted, with CO2 and ferts for about six weeks now.
 
Today I measured my tap water, and the PO4 is 2mg/l.

I also did the drop check thing on the other end of the tank, and while the CO2 is lower there, it's still green. The checker at the left side is green verging on yellow. And the right side is a darker green.

I had an idea. My diffusers often have CO2 bubbles 'burping' from the top. I got the extension units for it and they've helped, but there are still bubbles. So I've ordered two ceramic 'pollen' diffusers off ebay, and I'm going to run tubing from the tops of my current diffusers into the smaller pollen diffusers. I plan to place the new diffusers in my CO2 'weak spots'. So hopefully that'll even out things.

I'm going to go out and buy more test kits, test everything, and then I'll know once and for all what is going on in my tank. I'm beggining to suspect low K. But who knows...? I was suspecting low P04 earlier this week and that turned out completely wrong.
 

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