Need help on several issues!

[Patow]

Hey there,

I'm looking for some help on several issues I'm having with my tank. This system has been up and running for almost 9 months now. I've been through various algae blooms, and things seem to have stabalized the past few weeks. I'm wanting to start stocking my tank now as I feel comfortable that I'm through the worst of the "setup" blues. I'm very patient, and was in no rush to stock before I was comfortable with the system.

First of all, here are my current parameters:

System Volume: 200 gal approx (including sump/fuge w DSB)
Temp: 79.5
Sg: 1.026
pH 7.85 (@ lights on) - 8.05 (@ lights off)
Nitrate: 0
Phosphate: 0
Cal: 420ppm
Alk: 8.0
Mg: 1230ppm

I'm currently changing 20gal per week, and am topping up with RO/DI water. I'm toying with topping up with Kalkwasser to keep a few parameters in check between water changes.

Here are my issues:

1) My display tank sand has developed a few black spots on either side of the tank. Here are the pics:

Left side:

Right side:

I'm not sure what is causing this, and am wondering if more sand sifting/shifting creatures are necessary to keep the sand stirred and clean?

2) In my fuge I'm growing Chaeto. It's growing, but not very fast. The ball in there now as been growing for several months, along with other nuissance algae. I recently added some snails (turbo, astrea, nassarius) and an Emerald crab.

I'd like to get rid of the rest of the nuissance algae, and spark greater Chaeto growth. Any suggestions?

3) I added this coral about 4 months ago as a "test". It has grown very slightly, but not as much as I would expect. Could this be caused by low Alk/Mag? Any suggestions on how to spark growth?

4) Finally, I've got decent coraline algae growth on my glass and overflow, however, I can't get the coraline to grow on the rocks. They appear pretty much the same as the day I put them in the tank.

Anything I can do to spark growth on the rocks to hide some of my epoxy?

Appreciate any and all help on these issues! I'm really looking forward to stocking the tank, but would like to get these issues in check first.

If you need any other details on my system/equip, just let me know.

Thanks!

Dave

 

[reefnetworth]

to increase the coralline growth?
keep your Mg @ 3X's the level of your Ca. Alk should be at the high end, 10-11 dKH.

FWIW, A&H baking soda, one pound box per gallon of RO/DI mixed well.

cook soda @ 300F for one hour and slowly mix into one gallon of warm RO/DI, to raise your Alk.

 

[der_wille_zur_macht]

pH is a bit on the low side, as well as alkalinity - those two factors are probably inhibiting coral growth and coralline growth, as both are calcifying and need calcium, alkalinity, Mg, and pH at the correct levels to grow well. Your calcium value looks OK but alkalinity should come up a bit - likely that'll cure your pH problem, depending on the method you use to raise the alkalinity.

Check this list of chemistry articles for some really good references on the subject:

http://archive.reefcentral.com/forums/showthread.php?s=&threadid=102605

What do you have for lighting?

Also, at best, corals grow very slowly - so don't be TOO sad about that frag not sprouting like a weed.

What are you feeding the tank, if anything? What do you have for a skimmer? I'm wondering if your water is TOO clean for that chaeto in your sump to grow well.

Those black spots in your sandbed are nothing to be terribly concerned with - just don't disturb them. That kind of discoloration is normal in a deeper sandbed.

 

[reefnetworth]

my parms per Salifert kits,
Alk @ 10.5
Ca @ 470-475
Mg @ 1400-1425
N03 @ 3-5 max.
pH @ 8.4 diurnal (external intake to skimmer, i drilled a hole through the wall :lol: )

 

[Patow]

Thanks guys!

I went out and got some Kent Alkalinity Buffer. Did my first daily dose to start to boost it. Also dosed some Tech-M to boost the Magnesium. Will test again tomorrow and see where we're at.

I'll continue to dose both until I get my parameters in better ranges. I'll then re-start topping up with Kalkwasser to keep Alk and Ca in check, and keep my pH higher. I'll probably need to continue to dose Magnesium with my water changes.

For lighting, I'm running 2 x 175W MH, 2 x 110W VHO

My skimmer: Tunze 9010 Skimmer