Monti and Mille Help

[TheGent]

Hello --

I've been wrestling with this mystery for about 2 months now. All the Montipora corals I put into my tank (digitata and danae) loose thier color after a couple of weeks. The purple digitata is now a brown digitata, the pokerstar monti is now white with brown polyps. Neither of them are showing any tissue regeration, but there isn't any growth either. I also have a cap that was tan to begin with, thats still tan, so I can't guage any color change on him. I can't keep a millie for more then 2 weeks without RTN setting in, and it's gone in a day. Other SPS (acros/pocci/birdsnest) are fine and hold thier color.

The tank is a 12gal nano cube with a 150W MH pendant about 5 inches from the surface. Both monties are 1/2 up the tank (moved from the sand slowly over a few weeks), so a total of about 1ft from the light.

I've done quite a bit of research and first thought it was a phosphate issue (it wasn't, it tested very low). I then thought that my calc/alk was out of wack. The alk is at 7dKH and the calc is at 440. Both seem acceptible from what I've read. My pH is a little low (8.0) but it doesn't swing so I thought that it would be better to keep it stable then to have it start swinging around.

Everything else is where you'd expect it to be. No ammonia, no nitrites and very low nitriates (lowest that my test kit will read).

Are there any suggestions from you SPS guys out there? I've purchased additives thinking I figured out what was going on, only to run the tests and finding out I'm wrong. So far, I haven't dosed anything, except myself :beer:

Thanks for looking.. Here's the facts:

1. System age and size: ~9 Gallons of actual water, it'll be up a year next week.

2. System type: No protien skimming, 3 gallon water change each week. Modified the cube to do surface skimming (no scum on top of the water)

3. Water flow: Spray bar @290gph, and another 100gph pump in the tank to add turbulance

4. Filtration type: LR in backchamber along with Purigen.

5. Lighting photoperiod, scheme, color temp, type and wattage: 150W 14K MH pendant, 12 hour photo period.

6. Water parameters (temperature, calcium, alkalinity, salinity, ammonia, nitrites/trates, magnesium, etc.):
Temp 78-80 F
Calcuim 440 (as of last night)
Alk 7 dKH
Salinity 1.025
Ammonia 0
Nitrites 0
Nitrates <12 ppm
Phosphate ~0

7. Tank inhabitants (types of coral, fish, inverts, etc.): Cleaner shrimp, Orchid Dottyback. Various Zoas, torch, hammer, blasto and of course, the SPS

8. Type of water used for top-off/water changes: RO/DI

9. Additives used: Purigen, but no additional dosing

10. Feeding: Fish and shrimp get flake in the morning. Once a week (Day before the water change) I'll add oyster eggs and photo.

[ReefWreak]

That's why they suggest not using a nano (especially one that small) for SPS. You've got too much nutrients in the water. Use the trick to make the back a refugium with a light in or against the back wall. The LR and purigen don't help enough with nitrate reduction in so small a tank.

Alk is a little low too, but I'm almost 100% that it's a nutrient issue.

[ReefWreak]

I also think you're feeding too much. I fed my nano twice a week once I was comfortable with it's stability as far as nitrate reduction. Twice a week feeding with weekly water changes. It was a little bare, but it made everything grow really well and my one orange digi was bright. It's long since gone now, but here is the last FTS of my nano.

http://i15.photobucket.com/albums/a373/ericzombie/CIMG0353.jpg

I'm planning on getting the 150w 14k halide too soon, and I can't wait to see if my corals color up more because of it.

Just try reducing your feeding, and see how the nitrates go after two or three weeks...

[rstimeout]

I THINK YOU NEED MORE LIGHT

[TheGent]

<a href=showthread.php?s=&postid=9116760#post9116760 target=_blank>Originally posted</a> by ReefWreak
That's why they suggest not using a nano (especially one that small) for SPS. You've got too much nutrients in the water. Use the trick to make the back a refugium with a light in or against the back wall. The LR and purigen don't help enough with nitrate reduction in so small a tank.

Alk is a little low too, but I'm almost 100% that it's a nutrient issue.

Well.. The nitrates read 0, and the flake I add is literally 4 flakes, just so the fish is fed. If this was the case, wouldn't this issue effect all of the SPS, and not just monties and millies? Color on the other SPS is great, and there is growth there. I also have some red sea xenia that I added for nutrient export.

Thanks for the advice. I'm going to work on the alk issue. I'll also look into adding some macro in the back for additional nutrient export.

[ReefWreak]

The fish can go weeks without being fed, so don't worry about them. I guess if your acros are fully colored, then maybe it's just the alk. I just can't imagine keeping colored up corals in a tank that small while feeding every day. I fought SOOO hard to keep nitrates down in my 24g nano with powercompacts, but if you can do it, more power too you. Good luck, and I'll keep following this thread, or just the SPS thread in general to see how the tank comes out once you get the alk straightened out.

[RichConley]

Again, the whole "nano's dont need skimmers, and can get by on waterchanges alone" is absolute junk. Nano's need skimmers more than bigger tanks do. Waterchanges will never get you even CLOSE to where you want to be, unless you're doing 95% changes every 12 hours.

[ReefWreak]

Unfortunatly Rich, unless you build a sump for the nanos, I don't think that there is a good enough option for a smaller skimmer. At least AquaC came out with the remora nano, as it's I'm sure the best nano skimmer by far, however it's still just not up to par with the rest of the pack for in-sump skimmers.

I put a Remora Pro with Mag3 on my 24g for a few weeks, however it was just too damn big, took up like 1/4 of the tank with the pump and preskimmer box. It did do a good job though...

[RichConley]

You can run the mag external, and just pull from over the top.