What is Nutri-Fix NP?
Nutri-Fix NP is a bio media and bacterial food source adapted specifically for the reduction of Nitrate and Phosphate in aquaria.
How does it work?
Unlike indiscriminate and potentially risky carbon dosing regimens such as Vodka which entail adding carbon sources directly to the main aquarium to promote bacterial spread and nutrient uptake, Nutri-Fix NP is a 100% pure, fixed carbon source bio-polymer that can be used in a fluidised reactor for the promotion of rapid bacterial growth within a controlled environment away from the main display, promoting only those bacteria relevant to the task of nutrient uptake. The Bio-Polymer acts as a primary food source to encourage healthy bacterial colonisation which in turn assimilates or fixes Nitrate and Phosphate as that population grows. With these nutrients locked into the biomass of the bacterial population, this bio film or ‘bacterial mulm’ can then be exported via physical agitation of the media within a reactor to make way for further growth. The effluent carrying these bacterial films can then be directed towards the intake of a protein skimmer for physical removal via foam fractionation. Ongoing exportation of excess nitrate and phosphate are a direct result of this reaction.
By passing aquarium water through a fluidised reactor housing the bio-media, a fresh constant stream of both nutrient and oxygen can be supplied. Unlike alternate methods that encourage de-nitrification through anaerobic activity in a slow flow environment as a primary route to converting nitrate to free nitrogen gas, Nutri-Fix NP works in an oxygen rich environment by locking nitrate and phosphate into the rapidly growing bacterial biomass. Further nitrate reduction can also be witnessed as a result of underlying bacterial layers being starved of oxygen by several overlying populations. The removal of these layers via agitation to make way for further rapid colonisation is a crucial part of the process to prevent binding of the media via bacterial mucus secretion.
Do I need to do anything to the media before I use it?
A quick rinse in RO water or old tank water prior to use is recommended to wash off any fines that have developed in shipping, but no other action is required.
How Much Flow Is Required?
The flow rate required will be relative to both the amount of media used and the dimensions of the reactor it is housed in. Typically in a reactor of 100mm diameter using 1ltr of media, an input flow rate of at least 1500lph will be required to achieve effective agitation of the media. (See video link for visual reference)
How Much Media is required?
As with switching or adding any biological media to an existing aquarium, it is far better to start slowly and build up over time. Under normal operating conditions an average ratio of between 100 -200ml per 100lts of system volume is recommended. On first application it is recommended to start with approximately half the recommended amount and build up over several months to the required level. On new systems the full recommended dose may be used from the start to help limit future accumulations of dissolved nutrients.
Is it possible to use too much media?
No. Because the bacterial growth rate is limited by the availability of free nitrate and phosphate regardless of the carbon source being available, the efficiency of the media will fluctuate in tandem with these levels, allowing more colonisation as nutrient levels rise, and falling back as levels decrease creating a more stable environment within the aquarium. As previously stated however, it is recommended that a 50% dose is used when starting out on an existing aquarium to limit any excessive or rapid decreases in nutrient availability which could stress some more delicate organisms.
How often do I need to replace the media?
Because the media is consumed via bacterial action, its lifespan will vary according to the nutrient availability. In cases of low nitrate and phosphate availability, reduction of the media may be very slow compared to aquaria that have high levels encouraging more rapid bacterial growth. Under healthy conditions the media should only need topping up every few months.
Is it essential to run the reactor effluent to skimmer?
Ideally yes. Without the physical removal of the bacterial mulm, there is no pathway to remove fixed nitrate and phosphate from the aquarium. This will usually entail putting the reactor in line between the skimmer feed pump and skimmer itself. In cases where the skimmer feed pump exceeds the required flow rate through the reactor, it can be plumbed in via a bypass line which can be adjusted via an inline tap. (See Image below). In cases where a sump based skimmer is used, the reactor should be run from its own feed pump with the outlet directed towards the skimmer intake.
Will it hurt my corals if the bacterial mulm makes its way into the tank?
No. Any small amount that makes its way into the main display will simply act as a food source for any corals present. The bulk of the bacterial mulm should however be removed as a means of exporting bound nutrients.
My skimmer has stopped producing foam...Why?
In some situations when the media is first used, skimmate production may be adversely affected for 24-48hrs due to mild disruption to the surface tension of water passing through the skimmer. During this time the skimmer should be left to settle without any further adjustment to compensate. An adjusted skimmer may start to overflow once the surface tension has returned to normal and foam production resumes.
Will I still need to use Activated Carbon?
Yes. Bacterial filtration will not remove many of the adverse compounds and accumulations that good quality carbon can absorb, such as metals, organic dyes, or toxic chemicals released from corals as a means of chemical warfare. The use of a good quality carbon like RowaCarbon is still highly recommended although water clarity may improve with the use of Nutri-Fix NP due to the flocculent properties of the bacterial mulm.
Will I still need to use phosphate removing media?
In most cases yes. Phosphate found in foods is usually at far higher levels than nitrate. And whilst Nutri-Fix will reduce both Nitrate and phosphate in tandem, the process is a balanced one. Therefore excess phosphate will still need to be removed via the use of effective phosphate removers such as Rowaphos, although the need to replenish this media will usually be reduced saving money in the process.
Will it reduce the need for water changes?
No. Even with low levels of Nitrate and Phosphate, water changes still offer one of the best ways to balance the replenishment of minor essential trace elements, whilst diluting adverse accumulations.
Is the flow rate through the reactor crucial?
Yes. It should be remembered that Nutri-Fix NP is not an anaerobic filter media like Sulphur beads. Nutri-Fix NP works best under strong flow and aerobic conditions which will speed up the growth rate of bacterial populations and consequently the uptake of nitrate and Phosphate. The agitation and subsequent friction are also essential to free up fresh surface area on the media to encourage further bacterial growth. If not enough agitation is supplied, bacterial populations will overgrow and clog up the media, effectively cutting off the carbon supply from any further overlying bacterial growth.
How long will it take to see results?
Bacterial colonisation can take up to 4 weeks to establish itself fully to the degree that bacterial populations are high enough to effect free nutrient levels.
My nitrate level was falling rapidly after the first 4 weeks but has now slowed down?
This is a natural process. When free nutrient levels are high, rapid colonisation and growth of the bacterial populations is achievable, causing a fast initial decrease in available nutrient. As levels fall, the remaining bacterial populations have to work harder to obtain the remaining lower concentration of nutrients, as the level falls, so does the bacterial growth rate until such time as the nutrient availability reaches naturally low levels. At this point the remaining bacterial populations will be waiting to take advantage of any increase in nutrients, at which point their growth rate will increase in tandem to take advantage, offering a more balanced and rapid response to shifts in those levels.
I’ve been running the Nutri-Fix for several weeks now and my Nitrate isn’t falling ?
If phosphate levels are very low to start with (clear on high sensitivity kits such as the D-D phosphate kit) then these low levels may be limiting the bacterial colonisation preventing further nitrate reduction. In such cases it is recommended to try one of two things. 1:Take any phosphate removing medias offline for a short period to allow a small rise in background levels. This will help kick start the bacterial colonisation process. Once phosphate and nitrate have fallen back to low levels, the phosphate media should be put back online to take up excess phosphate addition above that which can be taken up by the bacteria. 2: Alternately, pursue a course of regular water changes to reduce the excess nitrate via dilution until levels are acceptable, at this point the bacterial colony should be able to take over and maintain a stable low level.
Will I be able to increase feeding of my aquarium?
Yes, one of the further benefits is that you can increase feeding of both your fish and corals if the NutriFix pellets are used in conjunction with a good phosphate remover like Rowaphos as together they will control the release of both Nitrate and phosphate into your aquarium so that you do not promote nuisance algae. Another product which allows you to “Feed Your Fish and Not Your Algae”.
Corals in the wild are adapted to live in conditions that have very low levels of dissolved nutrients such as nitrate and phosphate. These two nutrient sources are however essential for coral health at trace levels so we don’t want to remove them completely which would cause stress and possible bleaching due to starvation of the hosted symbiotic algae. There is however a large amount of locked nutrient available in the form of plankton in the wild which fulfils a major part of the corals nutritional needs via active capture.
NutriFix NP allows the aquarist the opportunity to lower and maintain free nutrients at more natural levels without the risks of complete reduction, whilst also allowing a gradual increase in the feeding of dedicated coral foods to enable a more naturally balanced uptake of energy which can result in better health, growth and colouration. In cases where nutrient levels have fallen to more natural levels, the introduction and use of various dedicated coral foods is strongly encouraged to ensure that they receive enough energy to thrive.