SPS tip recession

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Who has had this problem in the past and what was the cause?

The two I am finding most frequently are: Low Mg and a rusty screw in the water. Which I have/had both. My Mg was in the 1100's (nothing too worry about I would think) and I have a rusting screw in the water from the gate valve on my Euroreef Skimmer mod. (Which I am a little perplexed that a little screw could cause this much trouble......is GFO Fe(III) or Fe(II)....my memory fails me.)

I do use ROWAphos, but am stopping it to see if this helps.

Has anyone else had troubles with this?......I have been plagued with this for a few weeks.

I did a MASSIVE WC a couple of weeks ago and it subsided, however looks to be returning.

TIA, Doug

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Should have remember the old -ic and -ous endings......Ferric=(II) or +2 and Ferrous= (III) or +3

GFO is (II) and a rusty bolt is (III).

Its comming back to me now........

[dots]

This sounds familliar.......

http://archive.reefcentral.com/forums/showthread.php?s=&threadid=419143

[Justin74]

Polyfiber may give you a little piece of mind if your worrying about harmfull minerals and/or toxins. At least it would help you rule out a few things.



-Justin

[robertloop]

I had a situation when I suspected water contamination.. I went and got one of those poly filters. Most of the LFS cary them. Google that and you'll know what it is. If contamination turns out not to be it.. Try looking in the tank at night if you have'nt already. ;) Bad critters could be on the loose. If nothing else run a huge bag 'O' carbon for good measure..

Let us know! BTW... got any pics?

[tfp]

doug, how much rowa are you using and what is the flow rate thru the media? also, what is your phosphate testing at?

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I remembered that I used some Phosban with some ROWAphos last time and this could be the problem.

I have a Via Aqua plumbed to my reactor and quite honestly I don't really measure it, so much as make sure its not so much not to fluidize the carbon/GFO mix.

I have taken out the GFO and replaced the carbon. I will do a WC tonight and see if that gets things back in order.

As well, I will replace the metal screw with a nylon screw to eliminate that problem and start from there.

I hope it helps, some are starting to worry me.

[Marko9]

FYI, Galvanized screws do not rust.

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Galvanization, which uses Zinc either in a dip or electroplating oxidizes as readily....actually more due to electron affinity (electron negativity)...... as Iron. This makes it a sacrificial annode, rusting first saving the load bearing parent material. Overtime, the zinc will be depleated, grow thin and rust the screw underneath. In a saltwater condition, with the quality of plating on commercialy available screw I think it would be questionable for long term use........heck, most stainless rusts due to the lack of quality alloy used.

You can see this happening readily by looking at a roof with galvanized flashing. Ever notice how moss never grows below the vents.......the galvanization is disolved by the slightly acidic rain and runs down the roof, moss does not grow were the zinc runs down.

I think this may be toxic to fish as well, if I remember correctly.

Its just a gate valve knob, I will either replace it with a nylon or superglue the thing on there.