Why would I still need to dose PO4 and NO3 2.5 years after startup

russell.dexter · Jan 30, 2024

I have battled low nitrate and phosphate since I started my 36 gallon bowfront in July of 2022. (Upgraded to a 40 breeder about six months ago) I eventually had to put neo-nitrate and neo-phos on dosers (Kamoer X1 dosing pumps- total dose is spread out over 24 times per day) to keep up with the tank's demand in order to keep phosphate at 0.02 with hanna's ULR checker and nitrate and 5 with salifert's nitrate test kit.

Currently I am dosing 13mls of neo-phos daily and 10mls of neo-nitrate in order to keep the parameters as described. (I have also always battled low PH- and have only bumped it up to 8.0 in the day and 7.8 at night with kalkwasser dosing)

Additionally, I find that I have to up the dosage every few months to keep up with the demand of the aquarium . If I do not dose- I zero out within a week and the tank is over-run with chrysophytes. The aquarium does not have an algae problem as long as I maintain the dosing.

My question though is why? It seems that most reefers are having to carbon dose, over skim, underfeed, perform massive water changes etc to manage their nutrients. In my case however it has always been the opposite.

Why are some tanks always battling high nutrients and other tanks always low? I am trying to understand the process of what is happening inside my aquarium versus the next reefers?

Current Parameters:

Alk 8.5 (attempt to keep it at about 9) Tested with anna alk checker
Magnesium: 1400 (Red Sea)
Calcium 420 (Red Sea)
Phospate: 0.01
Nitrate: 3

I do have a lower bioload with two clown fish and a single damsel.

Salty_Northerner · Jan 30, 2024

How many corals and types could help understand what's going on. I have similar issues with phosphate dropping and use neophos while transitioning from TM pro reef salt to their bio-actic salt. It seems for me the system loves the salt now but there's some weeks I need to add phosphate till it sticks then it'll suddenly drop till I spend 2-3 days dosing till things settle out. My system is about 7 months old now but it's getting there. I do have alot of growth in a mixed reef so probably that's sucking it up. So far my nitrate is holding around 7-8 and also using the egg testers.

Klem · Jan 30, 2024

I’ve dealt with this before where I set up a new tank and battled low nutrients for a year or so until one day- pow - nutrients building and I stopped dosing. I watched them build until I had to control them. Then about 8 months later the aquarium turned around and started sucking everything up and I went back to dosing nutrients once again but at a lower rate. I attributed this to a bigger, more developed, bacteria colony in the tank. I ran the tank that way for years dosing a little, laying off a bit, and dosing a little.
On the flip side, the tank I have now, builds nutrients and doesn’t let up. I liked it the other way better. So I guess grass isn’t always greener on the other side?
My advise is to keep going, keep feeding, don’t clean detritus and hopefully nutrients will build…
PS, PH of 7.8 and 8.0 is fine. Sure it could be better but that won’t stop you from having a healthy reef.

Randy Holmes-Farley · Jan 30, 2024

russell.dexter said:
I have battled low nitrate and phosphate since I started my 36 gallon bowfront in July of 2022. (Upgraded to a 40 breeder about six months ago) I eventually had to put neo-nitrate and neo-phos on dosers (Kamoer X1 dosing pumps- total dose is spread out over 24 times per day) to keep up with the tank's demand in order to keep phosphate at 0.02 with hanna's ULR checker and nitrate and 5 with salifert's nitrate test kit.

Currently I am dosing 13mls of neo-phos daily and 10mls of neo-nitrate in order to keep the parameters as described. (I have also always battled low PH- and have only bumped it up to 8.0 in the day and 7.8 at night with kalkwasser dosing)

Additionally, I find that I have to up the dosage every few months to keep up with the demand of the aquarium . If I do not dose- I zero out within a week and the tank is over-run with chrysophytes. The aquarium does not have an algae problem as long as I maintain the dosing.

My question though is why? It seems that most reefers are having to carbon dose, over skim, underfeed, perform massive water changes etc to manage their nutrients. In my case however it has always been the opposite.

Why are some tanks always battling high nutrients and other tanks always low? I am trying to understand the process of what is happening inside my aquarium versus the next reefers?

Current Parameters:

Alk 8.5 (attempt to keep it at about 9) Tested with anna alk checker
Magnesium: 1400 (Red Sea)
Calcium 420 (Red Sea)
Phospate: 0.01
Nitrate: 3

I do have a lower bioload with two clown fish and a single damsel.

Are you using any nutrient export methods?

russell.dexter · Jan 30, 2024

Thanks for the feedback.

As far as soft coral:
1) I have a sizeable colony of trash palys and xenia
2) A large sinularia
3) Two nice colonies of random zoas

They have all grown from tiny frags to the point of being a nuisance.

SPS coral:
1) I have a bird's nest frag,
2) Green slimer
3) A tiny acro frag that has not grown much at all.
4) A chunk of duncan that has about a dozen heads.

I have only added sps/hard coral within the past year

For the first six months I struggled with soft coral growth- it was after I started actively dosing nitrate and phosphate that the coral growth rate increased. For months I tested and got zeros for both but was too nervous to start dosing. It was after my recurrent battles with chrysophytes that I went ahead and started dosing and immediately resolved the issue with chrysophytes and noticed significant coral growth for the first time.

In regards to nutrient export:
1) I have a small fiji cube sump and use filter floss for mechanical filtration changed twice weekly

2) A bag of chemi pure (not elite or blue but the original) in a high flow area. I change it every few months

3) Reef octopus skimmer. It takes about two weeks to get a full cup of skimmate (if I let it fill)

In the first six months, I tried to light a portion of the sump to run a refugium- that only made the issue worse. The cheato died because there wasn't enough nutrients to support it. (This was before dosing and monitoring my nutrients though) I have not tried macro since.

I test both nitrate and phosphate twice weekly to ensure I am not bottoming out.