Serious Algae/Cyanobacteria Problem

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The only phosphate in my tanks is from fish foods. If low phosphate encourages cyano, my tanks should be smothered.
Thereā€™s far more to the equation than that. For one, your tap water alone has enough trace phosphates in it for algae and plants to be competitive with bacteria. Secondly, your phosphates are not very low (IE in the order of 0.001ppm as it is many ULNS or those using chemical phosphate removers). Thirdly, food is not your only source of phosphates.
 
Hi guys sorry, it thinks itā€™s my fault we are moving off topic debating the need for phosphate. @ChefAlex @Byron i was recommending to dose phosphate on the basis he has massive nitrate levels in his tap water and has been using rowsphos to remove phosphate. He also has 0 phos showing in tap water. This should allow the surface plants to out compete the algae, thus also reducing the light through the water column. If this didnā€™t work we were onto mixing in some RO to remove the high nitrate but this isnā€™t quite a bit more work.

This is where I am not understanding the reasoning. I cannot understand how increasing phosphate could benefit Frogbit. I do not believe phosphate (phosphorus) in excess will have any positive effect. Citing from Peter Hiscock,

Phosphate is present in fish food, so levels are rarely deficient in the aquarium. In an average aquarium phosphate levels are frequently 1-3 mg/liter, while in natural conditions levels are normally only about 0.005 -0.02 mg/liter. Low phosphate levels are not normally a concern, but high levels can encourage algae to bloom. To grow strongly, algae require phosphate levels above 0.03 mg/liter; since these levels are usually exceeded in the aquarium, algae blooms are often the result. Under normal conditions, most phosphate is "locked away" in the substrate and unavailable to algae.

You cannot compare a wild system with an aquarium as the controls and inputs are so vastly different. However in relation to the above in a wild scenario where the phosphates are low so are the nitrates in a natural system and the excess harmful substances are removed by consistent water flow. .

The issue is see is the rowaphos extracting the phosphate from the water leaves the plants starved. Yes I also agree plants do prefer ammonia to grow but in our situation where we are removing ammonia with our filter media (the purigen in the tank) he is again removing the nutrient the plants need. The frogbit (floating plant) will be starved of phosphate as the rowaphos is removing that nutrient which restricts the plant growth, allowing algae to out compete it and thrive.

Potentially; removing the Rowaphos and Purigen and one of the lights, with the increased cleaning regime, and dosing of ferts - may right the tank on its own? We just want the advice to be consistent. @Byron would you agree with this course of action, then if after a week we aren't seeing improvements we can try a course of phosphate, if that fails then we are onto RO?
 
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Hi guys sorry, it thinks itā€™s my fault we are moving off topic debating the need for phosphate. @ChefAlex @Byron i was recommending to dose phosphate on the basis he has massive nitrate levels in his tap water and has been using rowsphos to remove phosphate. He also has 0 phos showing in tap water. This should allow the surface plants to out compete the algae, thus also reducing the light through the water column. If this didnā€™t work we were onto mixing in some RO to remove the high nitrate but this isnā€™t quite a bit more work.



You cannot compare a wild system with an aquarium as the controls and inputs are so vastly different. However in relation to the above in a wild scenario where the phosphates are low so are the nitrates in a natural system and the excess harmful substances are removed by consistent water flow. .

The issue is see is the rowaphos extracting the phosphate from the water leaves the plants starved. Yes I also agree plants do prefer ammonia to grow but in our situation where we are removing ammonia with our filter media (the purigen in the tank) he is again removing the nutrient the plants need. The frogbit (floating plant) will be starved of phosphate as the rowaphos is removing that nutrient which restricts the plant growth, allowing algae to out compete it and thrive.

Potentially; removing the Rowaphos and Purigen and one of the lights, with the increased cleaning regime, and dosing of ferts - may right the tank on its own? We just want the advice to be consistent. @Byron would you agree with this course of action, then if after a week we aren't seeing improvements we can try a course of phosphate, if that fails then we are onto RO?

Hi all,

Thank you again for all your help.

Today I have removed the Purigen and carbon, so all that is in my filter is filter foam and filter media. I have also turned off one light and will re program it to come on for 5 hours tomorrow.

I have also put black card on the back and sunlight side of the tank.

I am going to order some more TNC lite fertiliser as mine is almost empty.

I have looked at my phosphate test kit and it expired in March, but it has always read 0 mg/l to me, apart from in the original post test. Im going to order a fresh kit, any recommendations or is the one I have ok? I am also going to send my tank water and tap water off to some professional labs we use at work to test for phosphates and nitrates.

I have attached some updated photos below from today pre clean. They show the whole tank, floating plants and examples of the algae and cyano I have. It doesn't look like much, but ive been doing daily cleans and 70% water changes for just under a month now.

IMG_6171.JPG
IMG_6173.JPG
IMG_6174.JPG
IMG_6172.JPG
 
The JBL or sera phosphate kits work quite well and seem to be accurate for a hobby test kit.

The tank is certainly looking better than what it did though. Don't forget we wont solve this overnight! Remember to keep a photo log of algae growth so you can accurately measure it back day by day. This way you can see if the changes you are making are helping.
 
Hi guys sorry, it thinks itā€™s my fault we are moving off topic debating the need for phosphate. @ChefAlex @Byron i was recommending to dose phosphate on the basis he has massive nitrate levels in his tap water and has been using rowsphos to remove phosphate. He also has 0 phos showing in tap water. This should allow the surface plants to out compete the algae, thus also reducing the light through the water column. If this didnā€™t work we were onto mixing in some RO to remove the high nitrate but this isnā€™t quite a bit more work.



You cannot compare a wild system with an aquarium as the controls and inputs are so vastly different. However in relation to the above in a wild scenario where the phosphates are low so are the nitrates in a natural system and the excess harmful substances are removed by consistent water flow. .

The issue is see is the rowaphos extracting the phosphate from the water leaves the plants starved. Yes I also agree plants do prefer ammonia to grow but in our situation where we are removing ammonia with our filter media (the purigen in the tank) he is again removing the nutrient the plants need. The frogbit (floating plant) will be starved of phosphate as the rowaphos is removing that nutrient which restricts the plant growth, allowing algae to out compete it and thrive.

Potentially; removing the Rowaphos and Purigen and one of the lights, with the increased cleaning regime, and dosing of ferts - may right the tank on its own? We just want the advice to be consistent. @Byron would you agree with this course of action, then if after a week we aren't seeing improvements we can try a course of phosphate, if that fails then we are onto RO?

Yes, I am more inclined to agree considering the filter substances. Thanks. I am no chemist, and rarely get into these sort of discussions, but this came up in relation to the algae/cyanobacteria and I was attempting to help the OP.
 
I think there's a few misconceptions in the thread. I've used Purigen in the past and although it stains with detritus, I don't believe it stops decomposition and/or eliminates resulting ammonia...and it never reduced nitrates at all in my tank water.
We need to keep tank nitrates low and this is usually done with routine partial water changes...but this would be impossible with nitrates of 50ppm in source water.
As to nitrates in source water, as I've posted before...

It's not uncommon (sadly) these days to have high nitrates in source water, especially in agricultural areas. I have high nitrates in my well water I believe due to a 95 acre farmers field across the road that gets ample amount of manure and (I believe) some chemical fertilizer.

My home system does not generate enough pressure for an RO (reverse osmosis) system without adding a pump. Good RO systems aren't cheap and although they'll remove nitrates, you have to add minerals at additional cost.

I first invested in the now discontinued API Tap Water Filter (ION exchange resins). However, the use life of the cartridge for my water was such that it just wasn't cost effective. In a moment of inspiration, I wondered if I reclaimed a filter cartridge, and refilled it with API Nitra-Zorb, could I use it to pre-filter water for water changes. I put the question the API (Mars) Tech Support and they said that they did not know as the product had not been tested in that way. But they also pointed out that the resin use life is often compromised by detritus (Ah...but that would not exist when filtering clean well water!) (API Nitra-Zorb is an ION exchange resin that adsorbs nitrates. The beauty is that it is rechargeable with ordinary (non iodized) salt water, so it can be reclaimed many times. It is sold in pouches, intended to be used in filters.) I cut open several pouches to fill my Tap Water Filter with resin. It works awesome and I have filtered well over 8000 gallons and still going strong! Sadly the Tap Water Filter is no longer available and I'll admit that trickling water through a filter to remove nitrates is a bit of a pain. But for me, it's the most economical way to solve the problem.

I haven't used the Pozzani filter that @seangee used, but there are also other inline nitrate filters - but to my knowledge, none of these are rechargeable which make there cost in replacing cartridges high.

I think you'd be best served by taking every measure to keep tank generated nitrates low. You may need a filter to contain them, but you might get two or four pouches of API Nitra-Zorb so you have two in use and two recharging all the time. Ensure that they are put in the filter last after fine filter media so they see the cleanest water. With your water, you'll want to find the right amount of water for partial water changes to maintain an appropriate nitrate level in your tank.

Note: As the resin becomes less effective due to a detritus detritus coating it might be reclaimed using a 50/50 bleach/water treatment (like Sechem's Purigen) BUT I HAVE NOT TESTED THIS.
 
I haven't used the Pozzani filter that @seangee used, but there are also other inline nitrate filters - but to my knowledge, none of these are rechargeable which make there cost in replacing cartridges high.
You could try phoning Pozzani and asking what's in it :). I did once and the guy I spoke to was very knowlegeable and did give me the name of the resin used (sorry I can't remember but it was readily available in fairly large bags from other suppliers). I did consider DIY but as I need soft water anyway I decided RO was the best option for an easy life.

IIRC correctly I phoned to confirm that the ion exchange wasn't putting sodium into the water because that's bad for fish.
 
Purigen is very good at reducing nitrates, it doesnā€™t prevent decomposition but it will absorb the resultant nitrogenous waste from decomposition. We can see it partially working in the tank already as the nitrate in the tank is only 25ppm whereas the tap water is 50ppm. Granted plants are removing some but the only solution is that the purigen is removing the rest (or there was an inconsistency with the test result).
 
Purigen is very good at reducing nitrates, it doesnā€™t prevent decomposition but it will absorb the resultant nitrogenous waste from decomposition. We can see it partially working in the tank already as the nitrate in the tank is only 25ppm whereas the tap water is 50ppm. Granted plants are removing some but the only solution is that the purigen is removing the rest (or there was an inconsistency with the test result).
The marketing from Seachem is:
Purigen controls ammonia, nitrite and nitrate by removing nitrogenous organic waste that would otherwise release these harmful compounds. Purigen's impact on trace elements is minimal. It significantly raises redox. It polishes water to unparalleled clarity.

Other sources:
Although the organic precursors of nitrogenous compounds are absorbed, Purigen does not remove nitrate, urea and phosphate, so your aquarium plants still ..
And from Sechem Tech Support:
Purigen will prevent your nitrate levels from increasing any higher than they were before placing it in your tank (i.e. if your nitrates were at 10 ppm before you placed Purigen in the tank, once you place it in your tank it will not exceed 10 ppm from there on out). Prime binds to the nitrates and renders them nontoxic to your fish while allowing your bacteria to consume them. Prime can safely be used in a double dose every 2 days to help with nitrates (the 5x dose is recommended for nitrites, not nitrates), and again, the amount it helps remove will be dependent on your biological filter. Your test may still register as having nitrates present, but that is because there is no test that can distinguish between free (toxic) and bound (non-toxic) nitrate.
BUT I question this techie as he claims that BB removes nitrates and we know this is false!!!
 
Not sure if it's just me but that is highly contrary to the advertising and the sales blurb...

I used purigen before as I had 25ppm nitrate tap water. With it in I could always keep a stable 10ppm nitrate. That was my experience when using it but the above just doesn't make sense and he flips between toxic and non toxic nitrate? Very odd
 
Yes, I am more inclined to agree considering the filter substances. Thanks. I am no chemist, and rarely get into these sort of discussions, but this came up in relation to the algae/cyanobacteria and I was attempting to help the OP.
You could try phoning Pozzani and asking what's in it :). I did once and the guy I spoke to was very knowlegeable and did give me the name of the resin used (sorry I can't remember but it was readily available in fairly large bags from other suppliers). I did consider DIY but as I need soft water anyway I decided RO was the best option for an easy life.

IIRC correctly I phoned to confirm that the ion exchange wasn't putting sodium into the water because that's bad for fish.
The marketing from Seachem is:
Purigen controls ammonia, nitrite and nitrate by removing nitrogenous organic waste that would otherwise release these harmful compounds. Purigen's impact on trace elements is minimal. It significantly raises redox. It polishes water to unparalleled clarity.

Other sources:
Although the organic precursors of nitrogenous compounds are absorbed, Purigen does not remove nitrate, urea and phosphate, so your aquarium plants still ..
And from Sechem Tech Support:
Purigen will prevent your nitrate levels from increasing any higher than they were before placing it in your tank (i.e. if your nitrates were at 10 ppm before you placed Purigen in the tank, once you place it in your tank it will not exceed 10 ppm from there on out). Prime binds to the nitrates and renders them nontoxic to your fish while allowing your bacteria to consume them. Prime can safely be used in a double dose every 2 days to help with nitrates (the 5x dose is recommended for nitrites, not nitrates), and again, the amount it helps remove will be dependent on your biological filter. Your test may still register as having nitrates present, but that is because there is no test that can distinguish between free (toxic) and bound (non-toxic) nitrate.
BUT I question this techie as he claims that BB removes nitrates and we know this is false!!!
Not sure if it's just me but that is highly contrary to the advertising and the sales blurb...

I used purigen before as I had 25ppm nitrate tap water. With it in I could always keep a stable 10ppm nitrate. That was my experience when using it but the above just doesn't make sense and he flips between toxic and non toxic nitrate? Very odd


Hi All,

Thank you again for your insight !

I like the idea of pre filtering my tap water to remove nitrate so I have ordered API Nitra-Zorb. I will be able to install this inline by making a DIY canister that the hose from my tap connects to and then goes into the tank. I am thinking of also adding some Purigen in there, or is that pointless?

I have also ordered some JBL test kits to get more accurate results for phosphates and nitrate, amongst other parameters.
 
Hi All,

Thank you again for your insight !

I like the idea of pre filtering my tap water to remove nitrate so I have ordered API Nitra-Zorb. I will be able to install this inline by making a DIY canister that the hose from my tap connects to and then goes into the tank. I am thinking of also adding some Purigen in there, or is that pointless?

I have also ordered some JBL test kits to get more accurate results for phosphates and nitrate, amongst other parameters.
Iā€™m not familiar first hand with JBL test kits, but given their price and methods used I would consider using Hanna Instruments instead. They are tried and true tritiation test modules for professional industries but as an off shoot aquarists use them regularly. The price seems very similar to the JBL tests. As someone with a chemistry background I would trust Hanna Instruments for analysis but not JBL. Hope this helps in any way.
 
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Iā€™m not familiar first hand with JBL test kits, but given their price and methods used I would consider using Hanna Instruments instead. They are tried and true tritiation test modules for professional industries but as an off shoot aquarists use them regularly. The price seems very similar to the JBL tests. As someone with a chemistry background I would trust Hanna Instruments for analysis but not JBL. Hope this helps in any way.

We use Hanna instruments at work a lot for testing ammoniacal nitrogen and pH and they are very good. I wish we had tests for phosphate and nitrate i could use ! Thank you for reminding me.
 
I like the idea of pre filtering my tap water to remove nitrate so I have ordered API Nitra-Zorb. I will be able to install this inline by making a DIY canister that the hose from my tap connects to and then goes into the tank.

You will really need to trickle water through the Nitra-Zorb so it has sufficient residence time. Best to trickle filter into buckets or barrels...I now filter into a 45g Brute Trash can. Takes hours. but I can filter about 200g before needing to recharge.

I am thinking of also adding some Purigen in there, or is that pointless?
You can try Purigen in an attempt to lessen or prevent some tank generated nitrates...I just never saw that it made any difference in my tank.
 
You will really need to trickle water through the Nitra-Zorb so it has sufficient residence time. Best to trickle filter into buckets or barrels...I now filter into a 45g Brute Trash can. Takes hours. but I can filter about 200g before needing to recharge.

You can try Purigen in an attempt to lessen or prevent some tank generated nitrates...I just never saw that it made any difference in my tank.
Iā€™m not familiar first hand with JBL test kits, but given their price and methods used I would consider using Hanna Instruments instead. They are tried and true tritiation test modules for professional industries but as an off shoot aquarists use them regularly. The price seems very similar to the JBL tests. As someone with a chemistry background I would trust Hanna Instruments for analysis but not JBL. Hope this helps in any way.
You could try phoning Pozzani and asking what's in it :). I did once and the guy I spoke to was very knowlegeable and did give me the name of the resin used (sorry I can't remember but it was readily available in fairly large bags from other suppliers). I did consider DIY but as I need soft water anyway I decided RO was the best option for an easy life.

IIRC correctly I phoned to confirm that the ion exchange wasn't putting sodium into the water because that's bad for fish.
Yes, I am more inclined to agree considering the filter substances. Thanks. I am no chemist, and rarely get into these sort of discussions, but this came up in relation to the algae/cyanobacteria and I was attempting to help the OP.

Hi All,

My nitra-zorb and my new test kits came today. The results are below;

pH = 7.6
KH = 13 d
GH = 20 d
NH4 = 1 mg/l
NO2 = <0.01 mg/l
O2 = 8 mg/l
NO3 = 5 mg/l
PO4 = <0.02 mg/l
SiO2 = >6.0 mg/l
Fe = <0.02 mg/l
CO2 = 10 mg/l

My silicates are crazy high ! I have done some quick reading and they say that often they come from substrate in the tanks, but my tap water is also high. The description of the brown organics that they produce covering plants and substrate floor is exactly like what I get. Also the majority of my algae/cyano seems to come from around the base of the tank strongest.

What is the solution to this? Do I need to change my substrates? and is there a good addition to my filter you can recommend to combat this. I can't remember exactly what substrates I used, but they were a specific planting one that I put underneath my sand. All bought from my local fish shop, which is really good. How do I filter it out of my tap water, is there a way to do it without RO?

Are there any other things you notice in my water that is not good? Tap water measured NO3 as 10mg/l and SiO2 as >6 mg/l.

Also how exactly would I run a dilution test so I can see more accurately the SiO2 in my tanks?
 

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