give me a crash coral in small polyp stony coral care

[InAtTheDeepEnd]

I had a bunch of corals delivered today from jbsmarines (top seller if anyone is looking btw), all small frags, mostly softies but amongst them a leafy green pavona and brown plating montipora because I heard they are, so far as sps goes, easier..... I'm a bit nervous trying to care for these as I managed to kill my last sps by putting it too high in the tank and bleaching it.

Historically in this tank my calcium levels have been a bit on the low side (320ppm) with magnesium at 1425. I have started dosing seachem reef complete weekly. I don't know what NO3 and PO4 are right now but am planning on testing tomorrow.

The frags are on my sandbed right now and seem ok. My light is very very bright, allegedly 100 PAR at 60cm away. Not sure how far above the tank it is though. Is this too much? How often ought these corals be fed? (I use salifert coral food). 

Anything else I need to know......

[demonclownfish]

Well I'll say that 100 PAR isn't enough for most SPS - you want 200-300 depending on the locality and type. Monti's and Pavona are both rather forgiving and a little more bend to the rule - 100 might suffice but you'll see slow growth and poor coloration/polyp extension most likely. 

 

Also - the water surface cuts PAR value so you can't go by outside tank air PAR values

[InAtTheDeepEnd]

hold up, I think i gave stats for the wrong light 

 

[InAtTheDeepEnd]

Ok, so yeah....my original numbers were for my other light. The light I'm actually using produces LESS PAR.....pants. 

 

Are PAR values for different fixtures cumulative - ie, could I just add the other light to the tank as well? 

[mcarroll]

On 1/4/2023 at 3:51 PM, InAtTheDeepEnd said:

hold up

hold up 😉 

 

In the first place, "SPS" is not an ecologically descriptive term – it's mostly just a grouping of corals that look similar to us.  It doesn't tell you anything about a coral's particular requirements or preferences EXCEPT that it tells you that you're talking about a SPStony coral.  So you know it has a skeleton....which means Ca, alk and Mg dosing.  "SPS" doesn't tell you anything else useful.  Being SPS certainly doesn't tell you that the coral needs more light than other corals.  Read some of Dana Riddles articles on this myth (harder to find these days, but still available on reefs.com).....more is NOT better when it comes to lighting your corals.  Above around 100 PAR, other fundamentals are usually carrying more weight in terms of importance.  Soft flow and lack of dissolved nutrients are both more common problems.  Branching corals in particular (eg Acropora) benefit from stronger than average flow.  It's pretty common for tanks to be "lower than average" in general though...if you find detritus settling anywhere, that's a sign  

 

Second, the claim on your Amazon screenshot is 50 PAR at a depth of TWO FEET.  50 PAR is plenty for your sand bed, unless you plan on growing all your corals on the sand.  Not. 🤨 Plus, on nano-reef so your tank is not likely 2' deep (is it?)....so even your sand will have better than 50 PAR.   Your light is possibly just fine, IMO.   But what size is your tank?  (All dimensions.)

 

Last, actual lighting measurements at the surface of the water would be more useful than posted claims on Amazon.  Can you use a lux meter (or lux meter app) to get some measurements right under the light, at the suface of the water (in air)?

 

On 1/4/2023 at 1:38 PM, InAtTheDeepEnd said:

Historically in this tank my calcium levels have been a bit on the low side (320ppm) with magnesium at 1425. I have started dosing seachem reef complete weekly. I don't know what NO3 and PO4 are right now but am planning on testing tomorrow.

This is what should be bothering you/us more than the light you have.

 

320ppm isn't actually harmful per se, but how are calcium levels off before you even have corals?   Are those the levels you get from fresh-mixed saltwater?  (If not, then for comparison what are those levels?)

 

What about alkalinity?  This is more important than Ca or Mg.

 

Also, what is the salinity or specific gravity of the water you're testing?

 

If your PO4 and NO3 levels are off, corals will struggle or even die.  0.00 or numbers too near to zero are a problem – especially PO4.  Corals need available levels of dissolved nutrients after you get them in order to adapt and grow.  "available" means ≥ 0.05 ppm of PO4 and ≥5.0 ppm of NO3.  (PO4 is more crucial than NO3.)

 

 

[InAtTheDeepEnd]

Thanks, mccarroll. Really useful response!! 

 

I did a full run of tests today. I need to buy more test kits though - my magnesium test kit had fallen over and leaked so I could not test that

 

Sg 1.026

pH 7.9 (API)

TAN 0ppm

NO2 0ppm

N03 5ppm

PO4 0.3ppm

Ca 450ppm

Alk 10-11.5 (API said 10, Salifert said 11.5dH) 

 

I got a lux meter app and on the surface of the water it said about 1820 lux (readings varied a bit between 1819 and 1827).

 

Tank dimensions are 28 x 40 x 25.5cm

 

 

I already do have corals, though. Tank is stocked with a photosynthetic gorgonia, jasmine clove polyps, mini blue clove polyps, pulsing xenia, a blue mushroom, rainbow zoa, 2x red zoas, 1x rasta zoa, 1x toadstool, 1x cabbage leather, 1x leafy green pavona, 1x brown plating montipora, and 1x green plating montipora. 

Inverts are 2x dwarf blue legged hermit crabs, 1x strombus snail, 2x money cowries, 3x nassarius snails, some bumblebee snails, and loads and loads of dove snails, bristle worms, copepods, amphipods, other miscellaneous cnidarians I can't identify that came on the live rock when I added it. (LR was added August 2021). 

 

When I'm asking about "SPS" it's the montis and pavona I'm worried about. They have good polyp extension at the moment, though, but I'm not sure about the colour on the green plate.

[InAtTheDeepEnd]

Some random shots from today to give an overview. 

I overfed which is what made it a bit murky lol

 

Can I say it, but I think my lil reef is kinda cute lol 

[mcarroll]

On 1/7/2023 at 8:22 AM, InAtTheDeepEnd said:

Sg 1.026

pH 7.9 (API)

TAN 0ppm

NO2 0ppm

N03 5ppm

PO4 0.3ppm

Ca 450ppm

Alk 10-11.5 (API said 10, Salifert said 11.5dH) 

Sounds good, assuming those are fairly stable.   "0.3" for phosphate isn't really "0.03" is it?

 

On 1/7/2023 at 8:22 AM, InAtTheDeepEnd said:

I got a lux meter app and on the surface of the water it said about 1820 lux (readings varied a bit between 1819 and 1827).

Sounds low if that was right under the light at the water surface.  

 

Any chance there's a multiplier like x10 or x100 for the app's current setting?  

 

Or maybe the app was using the front camera instead of the back camera, or vis versa?  There's usually an in-app switch to control this.

 

Otherwise maybe try a different app.

 

You should be able to get something in the vicinity of what they claimed – 58 PAR / 3000 lux – as far away from the light as 2 feet.

 

On 1/7/2023 at 8:22 AM, InAtTheDeepEnd said:

Tank dimensions are 28 x 40 x 25.5cm

Going "by the math", and assuming your light has "standard" 90º lenses, you'd want your light no higher than about 15 cm off the water.  A little lower might be better.  Higher and you're wasting what power your light has by lighting up your room with part of it rather than lighting the tank.  (Bad for your eyes too.)