Please help: zero polyp extension and one RTN

creativesmurf

New member
Hey guys, really need some help here.

My corals have zero polyp extension with the exception of one, here's a breakdown:
Tank: 29g
Light: 1x250 HQI Geisseman, 12" above tank
Equipment: phosban, Precision Marine skimmer
Alk/Calc: slow drip fully saturated limewater + RH 2 part
~7-8dkh/350-400 ppm. I dose about 50-60 ml of the RH 2part daily. (the one that uses the baked baking soda)
Mg: unknown but I am dosing along with the 2 part
pH: 7.8-8.1
Temp: 79-81F
Salinity: 35ppm/1.025 (instant ocean with calcium supplement for water changes)

I am using multiple test kits (3 refractometers, 3 temperature sensors/Pinpoint monitor), Pinpoint pH probe + ph test kits, 3 different alkalinity tests, down to 1 calcium test kit. Phosban media and skimmer changed/cleaned monthly.

Happy:
New colony of green zoos at the bottom of the sandbed
Established birdsnest a the top of the tank
Orange Monitopora capricornis, three colonies, all have polyp extension

Sad:
Established tricolor, slow RTNing at the base
Established Tort Colony, advanced RTNing
New frag at bottom of tank, no polyp extension
Established Yellow scroll near top of tank, no polyp extension
Small Neon green slimer, small frag but beautiful and growing, no polyp extension

It has been like this for a long time, with no polyp extension, but now the RTN has been advancing up in the last 2 weeks. It's very slow but advancing. I had some really bad hair algae issues that affected some of my SPS but now the hair algae problem is much improved - but there's still some sticking to the body of the sps colonies. Hair algae alone has claimed like 25% of my tort colony.

I was dripping LW for a while and recently started supplementing 2 part because my alkalinity and calcium was constantly low. I think I might have not been gradual enough in my dosing and maybe the alkalinity swing kind of kicked the RTN in faster. I just pour it in slowly 2x a day (25-30ml per dose) into the tank. I know people say alkalinity swings cause RTN, and this is easily a 1.5-3dkh/day alkalinity swing.

I also have a pygmy angel that likes to nibble on the tort (but nothing else, for some strange reason) He's been doing that for a year. I'm thinking of having to get rid of him.

Any advice on next steps? Should I lower the alk/calc back down to where it was (5-7dkh/280-300ppm?) Get rid of the angel? More water changes? Argh...

Thanks for any help in advance.
 
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First if your not testing MG why are you dosing it?

Your problem is no doubt a water chemestry problem, or flow related.

I would also lower the light to 5-7" not 12".
 
Agreed on the Mg. If you read what RHF says about dosing, you will know that Mg, Alk and Ca go hand in hand. You appear to take great care in testing the other components, why not Mg??

What about flow, what do you have in that department??
 
Nitrate and phosphate levels would be nice to see. Also, what are the colors like on your SPS that are not showing the PE/RTN issues?

Also, looks like mostly Acro's are having the problem, maybe AEFW or redbugs?
 
Yeah, I know.. I need to test Mg.
Flow I have two Sea-flo modded maxijets pumping about 600+gph each (MJ600s)

I've never had nitrate problems but I'll test tonight along with phosphate.
 
I should say that I used to have a Koralia 3 + MJ900 + MJ1200 before I swapped over the the Modded MJets about 2 weeks ago. The flow is more random now and a little stronger but not enough to blow over the sandbed or cause problems for my little clown.
 
<a href=showthread.php?s=&postid=12385941#post12385941 target=_blank>Originally posted</a> by Husky_1
Nitrate and phosphate levels would be nice to see. Also, what are the colors like on your SPS that are not showing the PE/RTN issues?

Also, looks like mostly Acro's are having the problem, maybe AEFW or redbugs?

Color on the tort was and is still mostly beautiful, as is the slimer.. The tricolor has never been very colorful.. yellow scroll is not bright yellow but not too bad.. the birdsnest is brown but I think it was always brown to begin with. It has very slightly pinkish tips.. guess my light's too high... I can snap some pics tonight.
 
Ok, so by the colors your P04 and nitrate are not complete out of whack. Its not like everything in your tank is a nice shade of brown because the light is way to little, or nutrients way to high.
 
Just measured nitrate and PO4 (salifert test kits)
Phosphate is 0ppm (or just over... who can tell with these kits)
Same goes for nitrate.
 
i dont test magnesium either. i know it is important for photosynthesis and activates the electron transport in chloroplasts, but i figure that the salt mix (reef crystals) has enough mag to keep the tank happy. i do weekly water changes.
 
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