High Ca and Alk w/ Stagnant Growth

[Emhriverdale]

Hello!

 

I have a year old 55 g. I started putting in some LPS and SPS after success with some softies and frankly winning an sps pack on R2R. I've only recently started really monitoring parameters regularly since my freebies didn't immediately die (I was hoping to avoid being a hobbyist who spends all their time and money on a tank - lol nice try). 

 

My Ca has consistently been 500-550 on API and Hanna test, alk 10-11, ph 7.8-8.0. Nitrate and phos generally 0. I'm using Instant Ocean Reef reef crystals for 1.025 @ 80F. Lighting is 1 XR15 Gen 3, and 2 nicrew black boxes. Recently checked PARs and have good areas of 75-150 and 150-300. 

 

I have never dosed anything. I don't have much growth in some of the corals that have been around for a few months (montis, zoas), but everything looks relatively happy - see picture as I may not be defining happy appropriately.

 

Is my ph likely hindering uptake of ca and alk? If so, is air composition the missing variable? I'm repairing an octo 1000 but not currently running a skimmer. The sump is the basement w/ gas furnace and boiler, so there is definitely a CO2 source. 

 

Greatly appreciate any insights. 

 

[DaJMasta]

What is your stocking and feeding like?  It could be that nutrient levels are a bit too low (usually detectable but low is what people are shooting for and actually zero comes with some potential problems), and from the photo, there are not too many fish.  In the same sort of way that feeding contributes to coral growth, the presence of fish and the mess they leave generally helps things grow.

Otherwise, the missing parameter to check would be Magnesium - the Ca and Alk are pretty high for what most people run, but if the magnesium isn't similar, there could be a deficiency that's preventing growth despite plenty of the others.  I would think with those numbers that 1350-1400ppm magnesium would probably be about right (elevated, but by a similar amount as the calcium and alkalinity).

Also worth saying that corals often do just take a bit to settle in before really starting to grow - adapting to their new environment and whatnot.  A couple months is generally what I'd expect for that, but I've heard people say it can take longer, so as long as they're happy, there's at least not automatically something wrong.

[Emhriverdale]

I'm stocked with a yellow wrasse, 2 clowns, purple firefish, watchman, gramma, and a neon goby. I feed minimally - maybe 1/2 cube of mixed frozen ever 2 days. Huge pod population keeps the wrasse busy. Does this sound under stocked or fed?

 

I'll plan to:

• Check Mg
• Hold WC pending nitrate or phos increase

Is there any danger do having Ca staying that high? I have a background as an ICU nurse, and playing around with monitoring electrolytes is bringing back terrible memories. 

 

 

 

 

[DaJMasta]

That sounds maybe under capacity, but no, that's not understocked or underfed to a point where I'd think it would interfere with general nutrient availability.  I think many will agree that some detectable level of nitrate and phosphate is preferable to zero, but I don't know how big an effect it will have and depending on the range of the test kits, may not be all that different from zero readings (for example, kits that read to much higher overall values will have larger margins of error near the bottom of the scale which may mean a 'zero' reading is actually enough).  Waiting a bit on the water change is also probably a good diagnostic tool - if you just wait an extra few days or a week and then recheck alkalinity, any loss could be a direct indicator of stony coral skeleton growth, since alkalinity is generally the first parameter to deplete because of coral growth.

To my knowledge, 500ppm calcium should not cause a problem specifically.  It is not that dramatically elevated from normal suggested levels, and while it being high without magnesium or alkalinity may be a problem - it would generally just start to precipitate and sort of solve itself.  High alkalinity, especially in low nutrient environments, can cause sort of burns/bleaching, high magnesium can negatively impact snail health, but I think calcium would have to be a fair bit higher before it was really the direct cause of problems on its own.

[howaboutme]

I have high Ca in my tank, though I haven't tested in a long time so that could have changed. No issues, just let it come down naturally. I also use RC salt.

 

My only advice to you in regards to reef keeping (especially SPS) is that your goal is to prevent (or fix) problems, not to find them. Stagnant growth is not a problem. The picture of your tank looks great. Your eyes tell you most everything. Trust your eyes. Chasing #'s or problems is where issues start. Just go on R2R for examples! LOL. Good luck!