Nitrate wont go down

[so-smrt]

here is the deal 2m old tank 75 gal 50-60 lbs of rock 2.5 in of sand . 4 fish, a clean up crew and an emerald crab, everything bought at the same LFS, feeding every other day (1 cube of brine lasts about a week) did a 20% water change @ 1m did another 20% 10 days later did 50% a week after that. i have 2 large handfulls of macroalge. prior to the 2nd waterchange i did syphon out the sand and kinda stired it up. was that a mistake? also i i kinda sprayed out the bio-wheele but only a little bit :blush any suggestions!!! as far as i know there is nothing in the tank that could be dead or rotting so i would figure that is not is there anything i can add i saw products like "nitrate spong" and prime need help

[hobogato]

nitrate is the last waste chemical that has to be processed by your bacteria to finish the nitrogen cycle. with a shallow sand bed, it is impossible to siphon all of the detritus, so you will have a buildup of nitrate unless you have an anoxic zone in the sandbed (to do this, you need a deep sand bed - about 5"+), so the bacteria can finish the nitrogen cycle. the macro algae will remove nitrates from the water as it grows, but high phosphates can hinder its growth. are you using treated tap water as topoff? if so, your phosphates may be high which could hinder the growth of the macro algae and cause outbreaks of nuisance algae like cyano or hair algae. if you arent doing it already, you should start using RO/DI as topoff and for water changes.

[GaryP]

What exactly is your nitrate level? If this is going to be a fish only tank, nitrates will probably not be a big issue unless they are really high. The exception to this may be your clean up crew. Snails in particular can be sensitive to nitrates. Even in a reef tank, a level of 10 ppm is considered acceptable.

Without a deep sand bed you are going to be fighting a battle. Since you mentioned a biowheel, I assume you don't have a sump and if you have a skimmer, its probably an HOB. A tank that size really needs to have a sump and good skimmer. A good skimmer will probably help a lot.

Please let us know if we can help out with more info.

BTW, welcome to MAAST!

[Bill S]

As Ace says, try using RO/DI water. TEST YOUR TAP WATER for nitrates. Ours runs over 10ppm.

[so-smrt]

i use only ro water buoght at the stoer. i tested it and it was clean. i do have a sump i am using a Tide Pool (the one w/ the 3 trays for filter media and a bio wheele) that said it was good for up to 125 gal my nitrate is testing between 25-50 consistantly. how do i test for phos

[hammondegge]

it might be coming from your filter media. try removing that for a few weeks.

[so-smrt]

and w/o filter or replace it?

[hammondegge]

no filter. many prefer to run without filter media because it must be changed very frequently or it may quickly become a nitrate factory. i have never used it. some will put a micron filter sock on the overflow to the sump that is easier to clean. a bag of charcoal in the sump is more helpful than filter media IMO.

[GaryP]

If you are using filter media then it needs to be replaced or cleaned at least once a week. Anything in it that stays there just decays and contributes to the nitrates. Do you have a skimmer?

Testing for phosphates is a bit of a problem. The common tect kits only test for one kind of phosphate and there are two that are commonly found in water. The one the kit tests for is the less common of the two. The best way to test for phosphates is a good ole eyeball. If you see hair or other nuisance algaes you probably have high phosphates.

[so-smrt]

i left the bio-wheel in but removed the media 2 days ago and it seems to have started to go down. i am gonna do a water change tonight hopefully that will be the end of it. byt the way should i get some bio-balls or sm pieces of rock for the trays?

[hammondegge]

i dont think that would do you any good in the tray, but perhaps submerged in the sump. if you add about 30# of rock (doesnt have to be live right away) then i should think that you would need nothing else once the rock becomes seeded. rock, sand and skimmer can handle all of your filtration needs. add carbon and phosban specifically if needed.

[so-smrt]

after removing the filter media the nitrates have dropped a bit i have carbon but i understand it is bad for coral. also dont have a skimmer yet saving for a Percision Marine, i hear they are one of the best and localy made.

[hammondegge]

yep, get the skimmer next. it will make a very big difference.

[Louie3]

so CARBON IS BAD???????? FOR CORAL????????!!!!!!!!

[PeeperKeeper]

I had not heard that about carbon being bad for coral and I know lots of ppl with beautiful reef tanks who run carbon.

How is it bad? Removing too much from the water?

[Louie3]

i have carbon but i understand it is bad for coral.
Thats what that guy said. I'm just begining with corals and my first polyps where under carbon filtration for about 3 weeks
and just reccived alot more and i dont want them to die

[GaryP]

No carbon is not bad for the coral. Carbon removes dissolved organic compounds (DOC). We usually have an excess of DOC i the tank as a result of feeding and fish waste. I sincerely doubt you could ever get your DOC level down far enough to result in a negative impact.

High DOC has some bad secondary impacts as well. It will cause a lower redox potential and can cause a bloom of cyano.

[hammondegge]

not bad

[Bill S]

I HOPE carbon isn't bad. I've got something like 36 POUNDS on my tank...