Phophates and Nitrates

[ABreefkpr]

A friend of mine changed tanks a while back. He went from a 300 Gal to a 108. The problem now is nitrate levels. He always registered high phosphate levels in the old tank but now he's got high nitrates as well. He moved his sand, 100-150lbs live rock, fish and water into the 108 about 2 months ago and has had the nitrate problem ever since. The levels don't seem to be dropping. And no algae problem with the high phosphate levels. He had bio balls in the sump but took them out about a month ago. No change. I got some sand and water from him for one of my systems and I too have a nitrate problem. What could it be
Any ideas? Anyone

Keith

[martym]

Could of the move stirred up dead matter and started the cycle all over again?
Marty

[EmilyB]

He reduced his bioload accordingly with the move to a smaller tank??

[ABreefkpr]

Originally Posted by martym

Could of the move stirred up dead matter and started the cycle all over again?
Marty

That's what I was wondering, but after two months I thought levels should go down. I suggested he vacuum the sand.

Yes he has decreased the bioload. The tank used to be a predator tank with a shark, puffer, lion fish etc. Now he has about six fish including a regal tang, clown fish and a yellow tang. Corals number about the same or maybe as high as 10.
Phosphates as I have said were present in the old tank all along but with no algae bloom. Could it be his water? Levels aren't detected in 5 gal pail of newly mixed water, but could they be concentrated in 108 gals?

Keith

[Toooloud]

Being the kind of tank it use to be, He deffently caused a big cycle, there would be soo much crap in that sand bed, and he never had the issues before becouse he had 3 times the water volume so it was diluting it for him... What are his nitrates at? anything above 50ppm i would remove all the fish right away., anything less they have achance..

But a move that big.. he could be looking at up to 6 months..

When i moved from a 220 to a 90 i had the same issues.. 2 year old sand bed! .. moved to the new tank and it took my tank allmost 4 1/2 months before the water was compleley cycled to add my fish again!

[Jack]

Originally Posted by Toooloud

What are his nitrates at? anything above 50ppm i would remove all the fish right away., anything less they have achance..

Fish can tolerate fairly high nitrates it's the corals I would be worrying about.

What kind of sand bed did he have in the 300 gal? Crushed coral? This can trap detrius and cause nitrates. Also there is phosphates in some prepared food ie frozen cubes, flakes, pellets. You may of added really dirty sand to your aquarium.

Sounds like he has, or had, a FO tank but with corals. Sandbeds get really dirty with predatory fish because of the types and ammount of food. They are just plain messy.

Maybe he is overfeeding? You have to find the source of the nitrates and then fix it slowly by water changes, installing a refugium with DSB, or commercial de-nitrators etc. I dont know if those denitrators work all that well so I can't say, I've only heard.