2 Part dosing recommendations

rob G · May 19, 2016

Hello, I have a 360 gallon reef that is stocked with large sps. There are 4 base ball to softball sized birdsnest, one pocilliopora about soft ball sized. One purple Moni cap that is about 24" across and another red that is about 18" and two more that are about 12" each. There are a few small frags here and there but that is about it. I have been dosing BRS 2 part for some time. My son was born a year ago so the tank has been somewhat neglected but I am working on turning things around. Everything seems okay, the birdsnest have lost a little color and growth has slowed but no stn or anything (yet). My parameters are as follows,
ca 470
alk 5.7 dkh
mag 1300

I am raising my mag now, and working to get my alk back up to 8 or so. I have always struggled to keep my alk at the proper level and did the math again recently on daily usage testing at the same time in 24 hours. It seems I am dropping .8 dkh a day. This translates to 558 mls per day. Is this possible?? Also, why is my CA staying some what within desired parameters but not my Alk? Is low Mag to blame? I have always had to dose a bit more Alk than CA, I was dosing 5.5 mls of CA every hour and 7.7 mls of Alk every hour and it worked for a while and I just let it go. I didnt test again until I noticed growth slowed and birdsnests lost color. Any suggestions?

Thank you!

FLAdaboy · May 19, 2016

Hmm, I'm not a chemist but I'll take a shot. You might not have a huge calcium demand so the calcium you are adding may be buffering the all so much that you are needing to add. Is there a lot of coraline in your system? Do you have snow flakes in your water column? How often are you doing water changes (important)?

rob G · May 19, 2016

Thank you for your reply. I use Reef Crystals and change about 25 gallons per month, sometimes twice a month if time allows. I do see the cloud from alk additions form very small globules of white flakes that seem to slowly disappear (or at least sink to the bottom out of site) I have a bare bottom that is over run with xenia so it could just go there and sit. I dont see any deposits on heaters and only once every few months take the pumps out to clean the impellers of deposits so nothing abnormal there. There is a fair amount of coraline along the back and side walls but its not growing too rapidly. I read on some other forums that others with large tanks are dosing 300 to 450mls of each a day, that just seems like a large amount to me.

FLAdaboy · May 19, 2016

Larger systems may have more of a demand though. Here is where a chemist could chime in and discuss absorbtion of carbonates or bicarbonates as well as calcium in the water column.

FLAdaboy · May 19, 2016

On another note, your coral may be losing color due to either nitrates or phosphates. Lighting could be an issue as well.

rob G · May 19, 2016

I haven't checked nitrates or phos in some time so it is something I will look into. Lights are good quality leds that shouldnt be old enough to be degrading that much yet. But you are correct, otherwise that would be some where I should look. I will test for nutrients and see what I get.

Thanks!

FLAdaboy · May 19, 2016

rob G said:
I haven't checked nitrates or phos in some time so it is something I will look into. Lights are good quality leds that shouldnt be old enough to be degrading that much yet. But you are correct, otherwise that would be some where I should look. I will test for nutrients and see what I get.

Thanks!

Well the lights may be good. Something I have been guilty of is actually turning my lights up too high. I'm running radion gen 3 now on 50%. When I had Chinese fixtures back when led first hit the market, I had them at 100%. Just another thought.