Guys - here is a post which is emails back and forth with one of the technical guys from Red Sea. We will in June be having an evening with the Red Sea technical people at the Red Cow hotel so you can meet and ask questions as well as hear what they have to say. By looking over this post - you can see they know what they are talking about. This is in particular on the NO3-PO4-X product.
Question; We have a customer that is using your NPX for approx 2 months now. His nitrates are undetectable which is great but phosphates are off the scale.
Any ideas what must be going on as we still learning as we go with the product.
Answer: No3Po4-X is best looked upon as a food source for different types of bacteria, denitrifying (Heterotrophic) working on the No3 content and what we call PHB’s (Phosphate Harbouring Bactria) working of the Po4.
As you are already seeing in the system in question the bacterial colonies working on the Nitrate content reproduce much quicker that the PHB’s but in the fullness of time these levels will sync in relation to the No3 content.
What I am going to suggest in the first instance is you run the skimmer as wet as possible, wet skimate will help extract the Po4 laden PHB’s to be skimmed off as this is how the Po4 is exported from the system, No3 is digested by the heterotrophic’s and reduce this to free Nitrogen, Co2 and Water.
So the following Information will be most helpful.
• System Po4 level at the start of No3Po4-X dosing
• Colour of skimate coming from skimmer at the start and currently
• Type of skimmer and system volume.
• Current dosage of No3Po4-X per 100 litres
• Are you currently using any other form of Po4 remover
• All other test results would also be useful.
There is also the possibility of nutrient release from live rock that I can discuss but until I have the above information I won’t confuse things.
I look forward to the requested information so I can assist you further.
Reply:I have been using No3Po4-X for about 2 months now. When I started the nitrates were around 25-30ppm and phosphates 1.25. The last measurement i took, the nitrates were 6ppm and the phosphates were over 2. So it has been very successful with the nitrates
The tank is approx 425 litres including the sump. The sump only contains skimmer, heater and return pump.
I am not currently using any phosphate remover
I was previously using a v2 400 skimmer but switched to a deltec apf600 skimmer about a month ago. The deltec skimmer is producing a lot more skimate than the v2 ever did. Roughly half a skimmer cup is produced every 4-5 days, very dark brown in colour.
Dosage was initially 12ml per day, currently 8ml per day
When I started using the product I had a fairly bad algae problem, as you would expect from the nitrate and phosphate levels. For approx 3 weeks, ending about 2 weeks ago the tank went through a stage where there was absolutely no algae growth, never had to scrape the glass, no algae growing on the rocks. At the time the nitrates measured between 5-10ppm and the phosphates approx 1.75. It has since returned to normal levels of growth
Reply from Red Sea:
Thank you for the update.
The fact that you have seen an increase in your Po4 content suggests that you are experiencing some nutrient release.
When you start dosing No3Po4-X you can sometimes go through a transition process when feeding a carbon source(No3Po4-X), what this means is you actually go through a change of denitrifying bacteria as the stronger species being fed with the No3Po4-X takes over, this can produce some enzymes which are acidic, this acid is formed locally in the lattice of the live rock, the effect of this is to dissolve some of the Nitrate Carbonate and Phosphate Carbonate put down in the lattice of Corals ( live rock is of course dead Coral) these algae nutrients become available and are fed on by local algae, this can be seen as a local rapid growth of hair algae, you may also see a change in skimate colour, starting at a dark Brown/Green sludge this can become a bright light green and is due to the nutrient release, overtime this will change to a light tea colour once all the algae nutrient is expelled from the live rock.
The release of these nutrients can lead to a sporadic growth of hair algae, this growth of algae lasts whilst the nutrient is being released from the live rock, depending on the live rock this can last two to four weeks or sometimes longer in rock that has been in captive systems for many years.
Cyano bacteria (Red Slime) can sometimes be seen when the No3 to P04 ratio goes out of sync, this can sometimes happen if the No3 comes down too quickly, dosing of our Reef Energy A & B can usually resolve this issue.
I suggest increasing the No3Po4-X dosage back to 3ml per 100 litres whilst you still have high levels of Po4 present, it is important then to feed Reef Energy, this will ensure the corals have free Nitrogen available whilst you have low or zero No3 levels.
Questions from Seahorse:
Few more questions;
1. If people are using NPX biopellets and in some cases are not working as good as should or definitely not as good on the phosphate end of things – can they use NPX in conjunction with biopellets
2. Can they use pellets in conjunction with JBL BIONITRATEX which has encapsulated bacteria and encapsulated bacterial food within a bag and is a popular products of ours.
3. When someone is starting a new tank – how early do they add NPX
4. Can they use carbon and roaphos with NPX
5. Can you use UV with NPX
Response from RedSea:
Your welcome, I am always happy to help as best I can
1. We do not advise the use of Bio Pearls with No3Po4-X, the whole point of running No3Po4-X is to control the level of No3 & Po4 by this you can choose if you want a low nutrient level (No3 0.25ppm Po4 0.02) or rapid growth levels (1 to 2 ppm No3 0.08ppm Po4) with the use of bio-pearls you can take the levels to the point where no nutrients are present this has a detrimental effect on corals as they take 85% of their nutritional requirements from the Zooxanthellae living in the tissue of the corals, no nutrients no Zooxanthellae no corals.
2. No, for the same reasons as above.
3. We Use No3Po4-X in our new Marine Mature Pro kit from day one, so long as you have Nitrogen source like Reef Energy you can start from day one, the Energy is useful for the live rock anyway.
4. We actively recommend the use of good quality activated carbon, it is an essential part of any reef filtration system, carbon will not remove No3Po4-X or any of our Reef Colour supplements excessive Energy may be removed.
5. Yes, UV & Ozone can be used with No3Po4-X as this equipment as the light and gas only effect free swimming pathogens and bacteria, useful nitrifying bacteria are usually in contact with a surface area.
Summary:
Our customers tank is sort now and happy as pie. No more crazy algae growth and Phosphates and Nitrates are down to a low level and all corals are flourishing.
I know it's a long email trail - but thought it might be a useful read for some of the more advanced fish keepers.
Andrew
made it a sticky 
