No Nutrients, need suggestions

[mdorsty]

Hello everybody,

Long time lurker, first time poster. I have a several year old mixed reef that has been running very stable for awhile now. I've been doing so well with this tank I'm currently in the process of putting together a 200G to make more room for everything. However, just in the past few weeks I've been watching my Nitrates and phosphates disappear and a couple acro frags started to STN. (The acros have since started to recover) So I decided to start a campaign to raise nutrients up to where I really want them and this has proved to not only be a challenge but almost impossible at this point.

Display is 92g, 24g sump and a large 20g refugium with reverse lighting (high Co2 issues) and about 100g/h flow.
Temp 76.8-77.7
Cal 425 -Salifert
Kh 8 - Salifert
Mg 1350 - Salifert
Ph steady 8.1-8.3 24hrs - Multiple probes
Nitrate 0 - Red Sea Pro Nitrate's have been steady the last year @ 0.2
Phosphate 0 - Hanna Phosphorous ULR Phosphate has been very low all year at ~0.015

Where the problem started, got new lights... Went from 3 Kessil 360 & 4 48" T5's to all Orphek's. Had a very slow ramp up period of over a month, no nutrient issues or any issues really during this point. About a week after the Orpheks hit 100% the increase in coral growth was very noticeable, alk and cal consumption shot up then the nutrients dropped.

From this point I started to feed more homemade frozen food. Pellets are auto fed 4x/day already and the tank for the past year gets frozen food 1-2x daily about 2 cubes worth each time. This was increased to 3-4x day with no results for over a week while adjusting the skimmer down. I cannot turn the skimmer off, I have a CO2 reactor and Ph drops a lot when off.

The following week I decided I would clean the fuge out. It has been going gangbusters all year, can fill a 5 gal bucket with chaeto every other week the past year. I reduced the chaeto to the size of a baseball and cleaned as much of this other "unknown" macro algae out as I could.

A couple days later started to dose pure sodium nitrate (stump remover) and heavy Phyto feedings. This is where it gets interesting, I can get nitrates to raise and settle with hourly dosing, but PO4 always goes back to zero. So after a couple days with no success, I have disconnected the refugium and it has remained this way for the past several days. I put an air stone and a small heater in there just so nothing dies just yet.

Continuing the Nitrate and Phyto dosing without the refugium every single hour for 24hours a day. I initially was adding up to 40ml of phytoplankton an hour with no rise in phosphates. Finally after adding an entire 500ml bottle of phyto over 24 hours I was starting to see phosphorous on the Hanna, albeit 3ppb. I continued to do this for 2 days. Yesterday I thought I was finally winning, NO3 at .5 and PO4 13ppb I also dosed 2 vials of Biodigest to try and bring good bacteria back up. Today the Nitrate continues to rise and is currently 1 ppm but PO4 went down and is bouncing off of 0 again.

So... I have no idea what to do next. I can't afford to keep dumping copious amounts of food in the tank and test phosphate 12x/day much longer lol And now I have a disconnected refugium that's so full of pods it looks like its moving from across the room. Disconnecting the refugium has also caused my Ph to suffer, Ph reached 7.83 before the lights came on today and usually doesn't go below 8-8.1. Amazingly I have no weird algae outbreaks, dinos or cyano and everything seems to be taking the extra nutrients well, corals look happy. I went ahead and attached some front tank shots from today and also photos of the fuge and the mysterious macro that's on the rocks, I removed the chaeto for now. I'd like to get NO3 back up to 1-2 ppm and keep the phosphate in the redfield ratio.



Any suggestions really appreciated
- Mike

 

[Saltyreef]

You should look into www.greenleafaquariums.com.
I dose potassium nitrate and monopotassium phosphate for nutrient additives.
Make a stock solution and measure how much it increases the value of 1 gallon of fresh mixed salt water and apply that formula to your tank.
You dont want to be adding a lot of the things food contains just to bump up nutrients....
Pure phosphate additive will serve you better.
I agree you need to raise phosphate.
Nitrate just barely above detectable and phosphate the same. Just make sure phosphate is no less less than 15x lower than nitrate and you shouldnt encounter any issues from elevated nutrients.

 

[DangerDave]

I’m in the same boat OP. I have to dose nitrates. I’m using ME Corals product. I haven’t had low phosphates yet, but since my nitrates are up, my GFO usage has plummeted.

 

[Dom]

Hi Mike and welcome to the forum.

I want to begin by saying Thank You for such a detailed post. This level of detail will be most helpful in trying to assist you in achieving your goals. There are many talented people here along with some experts, so, I am confident you will find the answers you need here.

I too have been trying to get nutrients up in my tank over the last 3 weeks. At this point, I've removed all Chaetomorpha from my refugium and have turned off my skimmer.

I too noticed a small drop in pH when the skimmer was turned off, but was able to compensate by adding an air pump with a wood block to counter the loss of aeration the skimmer provides.

A 20 gallon refugium on a 92 gallon tank is big and will be better suited to your new 200 gallon build. I moved my Chaetomorpha to a holding tank with circulation and refugium light to sustain it while my nutrients come back up (as you have).

Once your nutrients are where you'd like, you could turn on the skimmer and reconnect the refugium, but in the end, I expect that you will be right back in the same place that prompted you to make this post in the first place.

Your rate of ALK and CAL consumption is likely due to the growth spurt you are observing since switching over to the Orphek lighting. This is probably true for the nutrient consumption in your tank too.

I think, in your case, the answer lies in dosing. And since I don't dose (although I too am thinking it may be time), I'll leave recommendations on that subject to members more experiences in that area.

I'll be following along for suggestions that may help me out as well.

Dom

 

[Salps]

I had the same thing happen when I had to start dosing P & N. It took several weeks of dosing and testing daily until I could keep them stable. First N balanced then 2 week later P did. My best guess as to why this happens is because you are changing the environment to favor different organisms. As they colonize they are using up the stuff you are dosing. Give it time they will balance.

 

[ckalupa]

Live Phyto? Possibly consuming some of the nutrients?

 

[mdorsty]

Thank you everyone for your helpful replies.

@Saltyreef - I will check out GLA, seems like I'm officially in the market for phosphate to dose. Seems obvious now that pure phosphate will probably be a more potent solution for my situation rather than excess food.

@DangerDave - Thanks I will check out ME Coral products as well.

@Dom - I think your right, I just need to start dosing PO4 & No3 as a daily regiment for this system. I'm so use to hearing most people have the opposite problem I guess I was having a hard time believing it.

I am still stumped as to why I'm having such a hard time maintaining PO4 though and I'm wondering if I have some kind of major bacteria imbalance going on. Even with the refugium disconnected I could add a large amount of Phyto (I tried 3 brands btw, Kent, Seachem & Brightwell) and a phosphate test 30 minutes later would show a large spike but then test again in another 30 mins and phosphate is back to 0. So I guess the next real test will be using pure phosphate. I ordered a bottle of Brightwell's phosphate product from Amazon yesterday, should be here soon. I will start dosing that this evening.

I also hooked the refugium back up last night as my pH was dropping faster than I'd ever seen it. It reached 7.79 this morning by the time the display lights came on, lowest i've ever seen it, which also caused my alk to spike to 8.8, so now i have to keep a closer eye on my alk doses.

I was surprised to see my nitrates had not dropped after running the refugium all night though! Nitrates still holding just above 1ppm, but still undetectable phosphates since yesterday afternoon even before the fuge hookup. So... this leads me to believe that my main source of nutrient reduction is mostly bacteria and not the algae in the fuge! I'm going to keep the fuge empty of chaeto and leave the fuge attached for now as I believe it is an integral part of maintaining pH for this tank. I just hope I can continue seeing positive results by dosing, like @Salps said I think continual dosing over time will "change" the bacterial populations.

I will keep everyone informed on the progress as I start dosing PO4. Thanks again for all your input.

 

[mdorsty]

@ckalupa - I added the phyto in hopes to raise phosphate without actually dosing pure phosphate. I added a lot! It would certainly be counterproductive if the phyto was eating the nutrients! But I was seeing an increase of PO4 shortly after every dose of phyto, unfortunately 30 mins later phosphate is back down to 0. I guess my thinking was if I pulled most of my nutrient export and then flooded the tank with nutrients for several days then my nutrients would test higher, but they haven't!

 

[ckalupa]

@mdorsty a quick spike may make sense. I culture my own phyto. The fertilizer that is used is nitrogen and phosphorus based just like regular fertilizers. If there is residual in the water with the phyto you may see a small uptick from that possibly. And then the tank algae’s and phyto proceed to consume. The phyto just like chaeto needs to die to release those elements into the water column. A slower process. Likely why some of the dry phyto food seem to do a phos and nitrate spike in the following 12-24 hours.