Reduce nutrients without growing algae?

Chrille26 · Oct 8, 2020

Hi! I decided to remove my refugium in which I grew Chaeto becasue it had a Cyano issue as well as some pests.
I like the clean look of the sump without the fuge, since my sump is relatively small and crowded, so now I am looking for alternatives to reducing excess nutrients without having to grow algae.
Right now I do the following:
Waterchanges weekly.
Liverock in dt.
Protein skimmer.
Liverock rubble and biomedia in the sump.
Avoiding excess food and overfeeding

The issue is my po4 is at 0,25 and my no3 at 10 ppm so I need to reduce it, but I would rather not dose anything to get it down, I am looking at a more longterm solution.
What is the best way of doing this without going the fuge, scrubber or reactor route?

Thanks for any advice!

Redfoxtang · Oct 8, 2020

Without using any type of media or algae and going the ole natural way would probably be doing daily water changes. Setup a pump depending on tank size to do a water change daily. That would be a good natural method. But maybe someone else has a better idea.

Shawn_epicurious · Oct 8, 2020

I have been struggling with phosphates for awhile now and have come to believe it is my over-feeding that is my primary issue. But there are other reasons... like I have a 12” Snowflake eel... I have not set up a refugium for the same reason you just took yours down... room... I am out of it under my tank.

Even daily water changes will only help so much. My RODI water comes out at .05 ppm on phosphate and by the time I mix my salt it is at .13 Already too high. I have been running PhosGaurd in a reactor and it has helped, but that is an expensive route! I am almost out of PhosGaurd. I am going to try Phosphate-E. I have not tried GFO yet or Kalkwasser.

IMO, you’ll have to export phosphates and nitrates in some way... dosing is all that’s left : )

Super Fly · Oct 8, 2020

can try carbon dosing.

Lets talk about Carbon dosing

Carbon dosing with emphasis on Vodka/Vinegar I had a little interest in Vodka/vinegar dosing from a couple people so heres a little write up of how I got started and basic info. I know that Vodka/Vinegar dosing has taken a back seat since the introduction of biopellets into the hobby but I...

www.reef2reef.com

FishTruck · Oct 8, 2020

Enough live rock (with enough age) and hungry corals can complete the nitrogen cycle and keep your phosphates down.

Good tip on making sure your RO DI is clear of phosphates!

Steady careful feeding will help balance things out. Algae, water changes, carbon dosing, GFO are not always necessary when tanks really mature.

Nano sapiens · Oct 8, 2020

How large is your reef aquarium and how many (and what kind) of fish? Fish and the feedings they require are typically the largest source of phosphate in the reef aquarium. The vast majority of the phosphate that a fish eats is excreted back into the system (especially if it is fully grown/mature).

Also, you can take a good look at your types of food and determine which are phosphate rich and replace with lower phosphate alternatives.

Periodically remove detritus from where ever it resides if it is heavy (clogged substrates do not function efficiently). Especially so for your live rock rubble as it is really food at collecting detritus over time.

Carbon dosing, done properly, has been shown to be effective at reducing nitrate. It can also reduce phosphate, but typically at a much slower rate than nitrate.

Basically, a lot of small steps and a patient approach can lead up to the desired lower nutrient results without having a refugium or using commercial products.

Saltyreef · Oct 8, 2020

your phosphate isnt abnormally high and if youre not growing hair algae everywhere, you have a lot of uptake by the other users.
I would just work on reducing nitrate through water changes. But keep an eye on rising phosphate.
I ran a really nice reef that always showed 0 nitrate and .01-.04 phosphate.

And now a not so nice reef @ 10 nitrate lol

FishTruck · Oct 8, 2020

Mechanical filtration with socks can also give you control. Based on how often you change them (or bypass them)... you can tweak your nutrients up and down.

FishTruck · Oct 8, 2020

Like salty said... your nitrates and phos aren't bad. If you have growing corals without an algae problem, I would be inclined to monitor it and intervene only if there are problems.

Belgian Anthias · Oct 8, 2020

Starting up a new tank one has to bring in nutrients as not much is in the water to cycle the tank.
After one has introduced an end-user, a fish, one has to feed it. Most of the food ( +-85%) is released as biowaste, it is remineralized, used by microalgae and bacteria for producing protein. Other organisms will feed on the protein, on bacteria and micro-algae. One has started a food chain. The fish may start to feed on the secondary organisms. If one continues to feed the fish daily as much as in the beginning not everything will be consumed. Once the tank is matured one may stop feeding the end-user ( the fish) as it may find what it needs. To support more growth one may feed the primary producers instead of the end-users. This way one can manage the nutrient content of the system easily, only what is needed is added, no waste.
I would not remove the refuge! It can be used for cultivating your primary or and secondary food source. Why not continue cultivating algae ( other than cheato) . Some cyano is an excellent primary food source.

Chrille26 · Oct 9, 2020

Thanks for all the replies! The tank is a year old and I do not have a algae issue at the moment. I have removed bryopsis and gha earlier with flux rx but that was some months ago and it hasnt showed up again.
Also my corals, mostly lps, are growing fine and not really showing signs of distress either, I just want to get the nutrients down to low levels and keep them there to mitigate future issues.

I bought socks and a sockholder today so I plan on running filtersocks with change every second or third day.
I will also read up on carbondosing since that seem like a well used and documented method.

bobbyM · Oct 9, 2020

Chrille26 said:
Thanks for all the replies! The tank is a year old and I do not have a algae issue at the moment. I have removed bryopsis and gha earlier with flux rx but that was some months ago and it hasnt showed up again.
Also my corals, mostly lps, are growing fine and not really showing signs of distress either, I just want to get the nutrients down to low levels and keep them there to mitigate future issues.

I bought socks and a sockholder today so I plan on running filtersocks with change every second or third day.
I will also read up on carbondosing since that seem like a well used and documented method.

Because you don’t have an algae issue at the moment, I would say you po4/no3 levels are ok. Bringing down po4 May benefit your coral growth. My suggestion is to find a small reactor like the two little fishies phosban reactor and run some GFO. BRS has the good stuff but only use 25% up to 50% of the amount they recommend in the directions. Their recommended amounts are for media bags and not the more efficient reactors. I change out mine every two weeks.

Super Fly · Oct 9, 2020

Chrille26 said:
Thanks for all the replies! The tank is a year old and I do not have a algae issue at the moment. I have removed bryopsis and gha earlier with flux rx but that was some months ago and it hasnt showed up again.
Also my corals, mostly lps, are growing fine and not really showing signs of distress either, I just want to get the nutrients down to low levels and keep them there to mitigate future issues.

I bought socks and a sockholder today so I plan on running filtersocks with change every second or third day.
I will also read up on carbondosing since that seem like a well used and documented method.

just be careful when carbon dosing... if ur levels are not bad it may do more damage then good, which happened to me and ended up losing few sps.

Belgian Anthias · Oct 9, 2020

Chrille26 said:
I bought socks and a sockholder today so I plan on running filtersocks with change every second or third day.
I will also read up on carbondosing since that seem like a well used and documented method.

Filtersocks soon become remineralization filters. Which must not be considered a problem.

Carbon dosing does not export nutrients! It facilitates fast heterotrophic growth based on using ammonium as a nitrogen source. The export depends of the skimmer, Its capacity to remove TOC and DOC. It is known a skimmer is not very effective in removing TOC and DOC, max +- 30%. (ref: CMF de Haes 2018) In the form of DOC, a lot of ammonia and phosphate is already produced to gain the energy to turn TOC into DOC. If the TOC export rate was insufficient before starting carbon dosing, it will not change when carbon dosing. What changes is the ammount of nutrients stored in bacterial bio-load as 40x more bioload must be produced to reduce the same amounth of ammonia compared to autotrophic based ammonia reduction. (ref: CMF De Haes 2017 Ebling 2006). As most carbon is turned into CO2 one must continue to add organic carbon to maintain the cycle. Exponential growth ends by exponential dead.
Adding carbonhydrates ( vodka method) may kill corals. (ref: CMF de Haes 2018 Anthias 2019)
If organic carbon is dosed based on the nitrate level, overdosing is not prevented. As mainly ammonium-nitrogen is used and the nitrate level is not representative for the daily nitrogen overproduction, ammonia may become limited available in the water column for all slower-growing organisms, including corals. Dosing carbon may mess up the existing biological balance, the carrying capacity shifts towards heterotrophic ammonia reduction and the carrying capacity may become dependable of the daily addition of organic carbon. If overdosed, this may end up in completely losing the previously installed autotrophic based carrying capacity. Once dosing carbon, returning to normal operation must be done knowing sufficient autotrophic caryingcapacity may not be available and it may take weeks for reinstalling.

If starting dosing organic carbon one best has an idea of the daily nitrogen overproduction and dose no more as needed to remove the overproduction, a bit more to lower the nutrient level present, and I would use the phosphate content as a safety parameter. Once started it takes weeks for building it of again safely. Use only products of wich you know how much organic carbon it contains, exactly. When using carbonhydrates ( vodka) or carbonhydrates based products, be sure not to overdose. Only use products of wich you do know what they contain, exactly.

Having a refuge one can easily manage nutrients by cultivating algae and feeding them with for the target nutrient modified food ( F2 media). This without messing up the existing balance.

ReefLab · Oct 9, 2020

I think my clarisea filter roller is the most efficient part of nutrient export

I’ll just mention that you should be cautions trying to lower NO3 and PO4. If you bottom it out for too long coral will die

HB AL · Oct 9, 2020

In my case LOTS of rock, skimmer and nopox.

flampton · Oct 9, 2020

Just an FYI but chaeto and other algae are a form of carbon dosing. They bring carbon into the system and build mass with the produced carbon and the ammonia/nitrates, phosphate and sulfate present in the tank. It's a little gentler though because algae are not very productive compared to heterotrophic bacteria. If you overdose you will get a bloom. Then depending on how well you skim it might last awhile. I personally recommend a UV on backup (I don't recommend 24/7 though because that defeats the point of carbon dosing in the first place)

Tldr dose carbon run a skimmer and be careful.

laverda · Jan 6, 2021

Shawn_epicurious said:
I have been struggling with phosphates for awhile now and have come to believe it is my over-feeding that is my primary issue. But there are other reasons... like I have a 12” Snowflake eel... I have not set up a refugium for the same reason you just took yours down... room... I am out of it under my tank.

Even daily water changes will only help so much. My RODI water comes out at .05 ppm on phosphate and by the time I mix my salt it is at .13 Already too high. I have been running PhosGaurd in a reactor and it has helped, but that is an expensive route! I am almost out of PhosGaurd. I am going to try Phosphate-E. I have not tried GFO yet or Kalkwasser.

IMO, you’ll have to export phosphates and nitrates in some way... dosing is all that’s left : )

Your RODI should have zero phosphates.