Did I screw up my rocks?

[Pete_the_Puma]

Hi all,

So after having a tank for a number of years back in 2005-2010 I had to move a few times. Now that I am finally settled in my new "long-term" house I had decided to reboot the tank.

Tank is a 65 gallon tall AGA tank, sump is 29 gallon tank and I would estimate total system volume at 85ish gallons.

So I cleaned everything and got some new equipment (LEDs are awesome no more changing bulbs!!). I had quite a bit of rock from previous tank that was dry and in a bucket in the garage for years.

I got 52lbs of live rock (Fiji`s Best Saltwater Aquarium Live Rock) and about 20-30 lbs of my old "dry" rock from the garage.

The live rock I put into a tub with fresh saltwater, a heater and a powerhead as soon as I got it, it stayed in there for a week and then I brushed off any detritus from it with a toothbrush and into the DT it went. It smelled great.

The old rock from the garage I soaked in distilled white vinegar for about 1 week, then I put it into a separate saltwater tub with a heater and power head for another week or so. I then brushed off the crap from it with a toothbrush. Now I could have been more diligent with the scrubbing here, most of the rock became a glistening white but there are certainly plenty of crevasses that the toothbrush could not reach...

I put all those rocks (2/3 Live, 1/3 old dry) into my DT with a shallow sand bed of live sand (Caribsea Arag-Alive Special Grade Reef Sand) and let the system run for about 10 days.

Ammonia came down to zero.

I have added 4 blue reef chromis. Now everything looks great, no algae and fish are eating and happy and skimmer is pulling a lot of crap but my phosphate and nitrates are consistently high!

pH 8.2-8.4 (cant remember the test kit, ATI I believe)
Nitrates: between 25-50 ppm (salifert) (not sure but it seems closer to 25)
Phosphate: 0.20-0.30 ppm (Hannah)
Temp: 77-78 F


Now I'm really not feeding the chromis all that much (a few flakes 1-2/day) and with such a low bioload and the fact the nitrate and phos were high even before adding them I do not think I can blame them for this. I am assuming the rock was not completely cured and there was still some stuff dying off from it causing high nutrients in the tank leading to accumulation of nitrates and phosphate? Is that eventually going to stop or should I try to pull the rock out and "cure" it the proper way?

I mean those levels are not catastrophic so I guess I could just wait?

I did a very large water change late last night (about 45-50 gal), will retest today. New water was painstakingly temp and salinity matched as not to traumatize the chromis...


Any recommendation is appreciated,


Pete

 

[seamonster124]

Nitrates will be high for sometime after cycle. I still have trace nitrates; 5 month old tank. You bring it down over a long time with water changes, skimming, refugium plants, etc.

Unlike nitrites, nitrates do not get to be dead zero unless you take some serious measures over a period of time.

 

[MondoBongo]

the rock could certainly be leeching phosphates back in to the water. you might want to run some GFO (granulated ferric oxide) for a while until those levels come down. if you can't get them down with GFO, you can look in to using lanthanum chloride, but that's more of a specialized substance that requires additional care and steps.

you could also try starting a refugium and exporting those nutrients that way if space permits.

in regards to the nitrates, they certainly could be high post cycle as seamonster suggested. they could also be up from organics, long dried, finally decaying out the crevices of the rocks. at any rate, i would just keep up with large, regular water changes to help get them down, and again a fuge would be great if space permits.

just as a sanity check, you are using RODI water for your top off and water changes with a reading of 0 TDS, right?

 

[MBMAX]

I restarted my tank with old rocks from my previous tank like you did.
I follow the advise of very experienced people in RC and I cleaned the rocks first with diluted bleach for a day or two and then with muriatic acid. This way you avoid N and P spike that sometimes will take a long while to decrease.

 

[Pete_the_Puma]

Thanks for the replies.

Of course I am using RO/DI with a TDS of 0. I have a nice new MaxCap RO/DI unit. Tested the water 2 different ways.

I have been reading A LOT and I think I will start dosing Vodka with a doser fairly soon and continue with the regular high volume water changes. Rocks cant leach forever can they?

Pete