removing to many nutrients killing SPS?

jedi31

Member
Okay over the last week some of my sps are starting to STN including my beautiful red planet colony. Here is my situation.
Water specs are
90 gallon tank
Cal 425 (Sailfert) Alk 7.7-8.0 (Lamont's) Mag 1350 this stays real stable (I have a litermeter)
Nitrates are under 1 (Sailfert) and Phosphates are 0.02 (Hanna)
Lighting is 2x 250 watt radiums about 2 months old
PH is 8.2-8.3 and salinity is 1.025- 1.026
Temp goes from 79 to 80 when lights are on so just a one degree swing each day. This has always been this way.
Tank is full of healthy fish that I feed twice a day. Mysis,Pellets. etc...

Tank changes the last month

Addition of a Regal Angel that is not nipping at the sps, he's actually eating mysis and pellets well. :spin2:

Upgraded my skimmer to an octupus pro reef rated for 2x my tank size.

2 weeks ago I started to add Biotim and Biodigest prodibio products to help keep my nutrients down. When I started my nitrates were 3 and Phosphates were around 0.03-0.05. I have dose one vival of each for the last 2 weeks and have not used the reef booster yet. Since I started to use this product some of my sps have started to stn and my monti purple plate looks very pale in color. I think despite feeding twice a day my corals are starving but not sure if this causes Stn? I feed oyster eggs every other night as well. I'm so confused because I heard nothing but good things using prodibio. How can my sps stn in stable water conditions?? Alk and temp are very stable. The only diff is the nitrates and phospahte have gone down a little which shouldn't cause stn.

These are the things I'm going to do to try tp stop the stn.

Do small water changes to help replenish trace emlements
Stop dosing Prodibio
Add reef booster to give the corals some food.
Check for iodine and potasium- I never check these.. can a lack of these cause STN?

Thanks for reading and helping me out.

Mike
 
I think thats a lot of BioDigest to be using that fast. I would try ever 2 weeks. I don't think its the fact that nutrients are to low, they just got stripped to fast. Real coral reefs have nutrient levels far below even the most ULNS.
 
I think thats a lot of BioDigest to be using that fast. I would try ever 2 weeks. I don't think its the fact that nutrients are to low, they just got stripped to fast. Real coral reefs have nutrient levels far below even the most ULNS.

Is that true? I thought the ocean had an natural average phos level at .03? Does the ocean have zero nitrates to?
 
Yeah I agree, I think you went too fast and that is what is causing STN, its pretty comon with alot of the ULNS system but they usually advise you to go very slow. You want to do this (depening on current levels) over the course of months and not weeks.

Although I do think it is possible to have 'too low' of nutrients, I have found it best to keep my P and N around .05. If you are dosing Amino's (which from what I understand is basically nitrate), you can generally keep it around this level with positive benefits without it rising.

However, I have seen some really nice reef with N and P in the .15 range and really bad one in the .02 range, so I would tend to believe corals absolutley need some amount of N and P to pull from, but too much will kill them.

My general guideline is to remove as much as I can through export so I can pump a ton of food back in. I feed very heavily.
 
Yeah I agree, I think you went too fast and that is what is causing STN, its pretty comon with alot of the ULNS system but they usually advise you to go very slow. You want to do this (depening on current levels) over the course of months and not weeks.

Although I do think it is possible to have 'too low' of nutrients, I have found it best to keep my P and N around .05. If you are dosing Amino's (which from what I understand is basically nitrate), you can generally keep it around this level with positive benefits without it rising.

However, I have seen some really nice reef with N and P in the .15 range and really bad one in the .02 range, so I would tend to believe corals absolutley need some amount of N and P to pull from, but too much will kill them.

My general guideline is to remove as much as I can through export so I can pump a ton of food back in. I feed very heavily.


shadowarmy touched on what i believe to be a very important topic: nutrient 'export' and 'import'.

you have increased your systems ability to 'export' nutrients. both good and bad nutrients are being 'exported'. you must compensate for the good nutrients being 'exported' by 'importing' more good nutrients.

i would suggest one of two things:

A) discontinue the addition of bioptim and biodigest, begin skimming dry if you are not already, and do a 25% water change. the water change will replenish your system with vital minerals and elements needed for coral health. discontinuing bioptim and biodigest and skimming dry will ensure that the vital minerals and elements you 'imported' via a water change, will not be 'exported' as quickly.


B) continue bioptim and biodigest. begin skimming dry if you are not already. begin additions of reef booster. purchase a K+ test kit and keep your k+ level at 380-400. begin 10% water changes weekly with a quality reef salt so to 'import' vital minerals and elements to your system. begin incorporating a balling light regimen to further 'import' vital minerals and elements to your system. and lastly take all these steps vary slowly.
 
All great info above. As a user of Prodibio for 1.5years, I can absolutely confirm too much too fast without some additional form of nutrient import can result in coral color lightening, tissue thinning and STN (at least in my system). Personally I would continue the biodigest and optim (reduce dose to every other week) but start adding booster twice/week. Your nutrient levels were already real low before starting prodi.

I dose 1 vial of booster twice/week rather than the recommended 2 vials once/week (270g system) I see better results this way and my skimmer doesn't go nuts when I start it back up either.
 
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I also tend to believe reef systems have 'reserve pools' of nutriets that are tied up in things like rock, sand, algae, etc.. I hear alot of people who start UNLS that after a week or so say "my N and P are undetectable", however they are struggling with algae problems or worse cyano. I think it has to do with these reserve pools.

People tend to not study their tanks and rely on test kits (too much) and start to pump in AA's, then the problem gets worse (usually when starting AA's the problem is compounded with cyano).

Like everything else reef, study your tank, it will tell you what is needed and go slow. Test kits wont tell you about phosphate that is tied up in algae or these reserve pools. The two hardest words to understand in reefkeeping seem to be patience and balance.

Watch your corals, assuming lighting requirements are met, darkening of corals usually means something is off in the nutriet area.

Lightening of corals (usually) means your reducing your nutrient load but to light means you are starving your corals.

You want to follow the progression and not go from dark to white, you want gradual change.
 
This is a lot of good information. I def went to fast with the carbon/bacteria dosing. I will keep dosing but will do it every other week. I also will do 10% water changes using Tropic Marin salt and feed reefbooster once a week. Sounds good? Thanks for all the info..

Mike
 
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