Phosphates stuck on 0 in new tank

[ReefSlice]

I set up a 40 gallon tank 3 months ago (rocks cycled in a bin for a month before that), and for the first month or so phosphates were staying between .05 and .02, nitrates were 3-10. Corals all looked great, coralline was spreading from frag plugs. Then about a month and a half ago, I had an algae bloom that is slowly receding, but my corals all paled out, coralline stopped spreading and started chipping away, and my phosphates bottomed out to 0. Since then, I've stepped up my feeding (3 fish) to twice a day with LRS reef frenzy, and just recently started dosing Red Sea AB+ every other day to see if it made a difference. Today my Nitrates sit at 9.1, and PO4 is still a steady 0, both checked with hanna checkers (po4 ULR checker and no3 HR). My coral are all still pale, growing slowly and a few zoas have been staying closed up. I'm also getting tiny patches of cyano showing up. I'm trying to find out my best course of action to get some PO4 into my tank. I'm assuming my dry rock is absorbing it like a sponge at this point, strange how it was steady at first though. Should I be dosing neophos until my PO4 evens out or should I change something about my feeding schedule? I'm feeding a lot right now for a young tank with 3 small fish, probably a 1.5x1.5" chunk of LRS, 25 ml phyto daily and 6 ml of AB+ every other day. I feel that my nitrates are starting to rise a bit because of my heavy feeding and leaving my socks in a bit longer. What would you guys do in this situation to get color back in my corals and everything back on track? I've also been keeping up with a 10-15% water change weekly, not sure if I should back off on that.
Other parameters are: Alk 8.2, Calcium 420, Mag 1450.

 

[Ashish Patel]

You have a skimmer? I would turn it off for maybe 1 day and get the PO detectable.
I would also stop doing those large water changes, your just removing more valuable nutrients.
Personally i never liked waterchanged just for the sake of doing them - If its needed then its great but new systems which is nutrient deprived it will create more issues like dino, pale corals, etc.

Feed aminos more too! that helps.

 

[ReefSlice]

You have a skimmer? I would turn it off for maybe 1 day and get the PO detectable.
I would also stop doing those large water changes, your just removing more valuable nutrients.
Personally i never liked waterchanged just for the sake of doing them - If its needed then its great but new systems which is nutrient deprived it will create more issues like dino, pale corals, etc.

Feed aminos more too! that helps.

I do have a skimmer, I turn it off for a few hours a day after feeding/aminos. Thing is, I feel like my nitrates are right where I want them, any higher would be unnecessary, and they're pretty stable with my routine, the aminos haven't seemed to have made a difference in color although it has only been 2 weeks. It's just my PO4 that won't come up off 0 regardless of feeding, aminos, or turning off my skimmer. I'm unsure if there's a food that may be higher in PO4 in it's nutritional ratios, or if dosing PO4 would just be my best option at this point?

 

[Tbg299]

I set up a 40 gallon tank 3 months ago (rocks cycled in a bin for a month before that), and for the first month or so phosphates were staying between .05 and .02, nitrates were 3-10. Corals all looked great, coralline was spreading from frag plugs. Then about a month and a half ago, I had an algae bloom that is slowly receding, but my corals all paled out, coralline stopped spreading and started chipping away, and my phosphates bottomed out to 0. Since then, I've stepped up my feeding (3 fish) to twice a day with LRS reef frenzy, and just recently started dosing Red Sea AB+ every other day to see if it made a difference. Today my Nitrates sit at 9.1, and PO4 is still a steady 0, both checked with hanna checkers (po4 ULR checker and no3 HR). My coral are all still pale, growing slowly and a few zoas have been staying closed up. I'm also getting tiny patches of cyano showing up. I'm trying to find out my best course of action to get some PO4 into my tank. I'm assuming my dry rock is absorbing it like a sponge at this point, strange how it was steady at first though. Should I be dosing neophos until my PO4 evens out or should I change something about my feeding schedule? I'm feeding a lot right now for a young tank with 3 small fish, probably a 1.5x1.5" chunk of LRS, 25 ml phyto daily and 6 ml of AB+ every other day. I feel that my nitrates are starting to rise a bit because of my heavy feeding and leaving my socks in a bit longer. What would you guys do in this situation to get color back in my corals and everything back on track? I've also been keeping up with a 10-15% water change weekly, not sure if I should back off on that.
Other parameters are: Alk 8.2, Calcium 420, Mag 1450.

Dose some Tropic Marine Plus-NP. I've been using it with great results.

 

[Ashish Patel]

I do have a skimmer, I turn it off for a few hours a day after feeding/aminos. Thing is, I feel like my nitrates are right where I want them, any higher would be unnecessary, and they're pretty stable with my routine, the aminos haven't seemed to have made a difference in color although it has only been 2 weeks. It's just my PO4 that won't come up off 0 regardless of feeding, aminos, or turning off my skimmer. I'm unsure if there's a food that may be higher in PO4 in it's nutritional ratios, or if dosing PO4 would just be my best option at this point?

I guess every tank is different. I have the opposite problem. Have to dose nitrates even when my phosphates are .3ppm or always too high. My new system I have very high no and po in balanced proportion. Don't be afraid to turn of your skimmer for 12 hrs per day of full day. Po come from fish waste and other organics from your rock and sand. Along as it detectable you should be fine.

 

[Ashish Patel]

You will have to wait few days to weeks to see if it's making a difference but you could also reduce photoperiod or intensity for a week and see if that helps. Could be too much light. Corals can take more Par when they have more nutrients. So if my nutrients go too low I first would reduce my intensity and then adjust my skimmer or refugium photoperiod and test accordingly

 

[ReefSlice]

You will have to wait few days to weeks to see if it's making a difference but you could also reduce photoperiod or intensity for a week and see if that helps. Could be too much light. Corals can take more Par when they have more nutrients. So if my nutrients go too low I first would reduce my intensity and then adjust my skimmer or refugium photoperiod and test accordingly

I did exactly that, the tank is lit by 2x kessil a360s coupled with a 4 bulb Aquatic life hybrid fixture. I dropped my kessil intensity down and reduced them to be on for just 5 hours a day, all 4 t5ho bulbs are on for 7, and just one blue+ and one actinic bulb on for 9 hours total. Didn't make any noticeable difference. I'm thinking the rock and sand in my tank sucking up phosphate has to be the issue here, I'll try slowly dosing some daily. Thanks for the input!

 

[Ashish Patel]

I am having similar situation in my holding tank. Started when I removed fish and did a big clean up. Things started paling fast so reduced my intensity significantly and added a large fish. It's a pain waiting for some positive feedback but testing alk against your consumption is the best way to see if your on the right track. Hanna ulr po checker is spot on and I never doubt the results. Try reducing your skimmer line and getting more dry skimmate that usually leaves more nutrients in the system

 

[Ashish Patel]

I did exactly that, the tank is lit by 2x kessil a360s coupled with a 4 bulb Aquatic life hybrid fixture. I dropped my kessil intensity down and reduced them to be on for just 5 hours a day, all 4 t5ho bulbs are on for 7, and just one blue+ and one actinic bulb on for 9 hours total. Didn't make any noticeable difference. I'm thinking the rock and sand in my tank sucking up phosphate has to be the issue here, I'll try slowly dosing some daily. Thanks for the input!

Give it some time. I really like seachem products for dosing nitrates. Very concentrated so last a long time compared to other brands. I may order the po for my fish less Qt tank

 

[ReefSlice]

Give it some time. I really like seachem products for dosing nitrates. Very concentrated so last a long time compared to other brands

My bottle of Flourish should be here tomorrow, plan on dosing the equivalent of .03 PO4 daily until it starts to stabilize as any registerable amount after 24 hours from dosing. Hopefully that puts me in the right direction!