nitrates/spiney box fish, severl questions

[dannyboy]

my tank has been "cycled" for several months now but I can't seem to get completely rid of my nitrates! We lost a spiney box fish and was told they are very sensitive to nitrates. LFS said vacuum sand out well for nitrates lurk deep in them. I thought I read not to vacuum the gravel cuz of the benificial life living it, but I did. I did the best I could for I have over 90 lbs live rock in the way. I moved the easy pieces but can't see disrupting the sea-scape I created from stacking. I have 75g w/ 29g sump/fuge, 90lbs live rock in main tank, prob another 20 in fuge w/ 4.5 inch deep sand bed and much cheato and a coralife 125 skimmer. So here are a few questions I have...
1) should i or should I vacuum the gravel
2) should I move more live rock into fuge so can vacuum easier
3) is any amount of nitrate acceptable
3) any advise on the box fish? my GF really loves these guys
Thanks for any advise in advance

 

[Bifferwine]

Do you have sand or gravel? Sounds like you have sand.

I would not vacuum out the sand. Yes, nitrates can be trapped in the sand bed, but until you vacuum it and disturb it, those nitrates are trapped. In an anaerobic environment at the bottom of that sandbed, the nitrates are converted to nitrogen gas (harmless). That's the purpose of deep sand beds, to naturally reduce nitrates.

You are correct that vacuuming out the sand can also harm your beneficial bacteria population. Keeping an ample amount of burrowing animals like nassarius snails is effective at keeping the sandbed clean of detritus that can cause nitrates.

Basically, the sandbed is not causing your nitrate problem, and disturbing it will only make the problem worse.

Now, if you have crushed coral, that could definitely be leading to high nitrates as crushed coral consists of larger particles and traps a ton of crap and detritus. And the sand sifting animals don't like to burrow or dig in it, so it doesn't get cleaned. If you have crushed coral, it's best to remove it all and replace it with aragonite sand, or else your problems will just get worse down the road.

Generally, nitrates under 20 are fine. You don't say what your levels are. If you have corals or anemones, they should be as close to zero as possible. But fish can handle much higher levels of nitrates than than (in the 100s). But I'm not saying that nitrates that high are good or okay; the lower the better.

No advice on the boxfish. They are extremely difficult fish to keep alive, even for the most experienced aquarists. Those things drop like flies and it's very rare that one can be kept successfully. Try to get your girlfriend to take a liking to a fish that is more suitable for keeping in captivity. Some animals should be left in the ocean.

 

[Bifferwine]

One more thing, you should figure out where your excess nutrients are coming from. The most common sources:

- pellet or flake foods (you should only feed frozen!)
- overstocking with too many fish (too much pooping going on)
- overfeeding (leftover food rotting)
- not using RODI water (nitrates and phosphates are introduced into your tank during water changes or when you top off for evaporation)
- using biowheels, bioballs, wet/dry or canister filters
- insufficient filtration (a good protein skimmer is a must)

 

[dannyboy]

I have aragonite reef sand, the "live sand" petco sells. In main tank it's only 1-2 inches deep depending where ya check, the fuge is much deeper. My nitrate reading is about 10, maybe 15 at worse case. I have a really small horse shoe crab, maybe 2 inch diameter that spends most of it's time buried, thats the only thing I have that buries itself. As of now, we have a second box fish, a small niger trigger, and a small clown goby, no coral, many hermit crabs/turbo snails, few emerald crabs in fuge. Is my tank fine and the box fish is just too hard to keep maybe?

 

[Bifferwine]

the box fish is just too hard to keep maybe?

That's what I'm saying.

Nitrates at 10 or 15 are fine for everything else in your tank.

 

[dannyboy]

I was buying ro/di water for most of this tanks life and have been having such bad luck gave up on that and have been using tap water treating it with "stress coat" to remove chlorine/chlorimines for about 2 weeks now. I had a coral beauty that did great for 2-3 months then took a turn for the worse. After the loss of him and the first box fish was on the verge of giving up so started using tap water. No phosphate or copper was detected. It's tough seeing my cichlid tank thrive so much and my salt water tank doing so poorly.

 

[reeffreak]

I doubt if the RO water could of caused the problem.Did you test the RO water and found something not right about it?Most people would be happy to be able to keep nitrates below 20ppm,even up to 50ppm is acceptable in most cases for a fish only system.IMO,you've done nothing wrong,boxfishes are super difficult fish and many experts who been in the hobby many years can't keep them alive longterm.Many websites list them as ''expert only''.

 

[dannyboy]

Naaaa, the ro water tested fine, so did my tap water, was expecting a lot of agle growth though. Trips to the lfs for water was getting old when my cool fish were dying anyways. Maybe the lfs are the prob then. I been doing everything right as far as i can tell, the box fish must just be too hard to keep in this environment. I have so few fish it looks so barren! My emerald crabs are starting to reproduce, lol.

 

[Bifferwine]

I would switch back to RODI water, it's still going to be better than tap water. Not to mention, using Stress Coat will screw with your filtration system. I used that stuff once and it put my skimmer out of commission for 2 weeks.

Try getting RODI water from somewhere else. You can also get it at Walmart or any grocery store. Believe me, using tap water will come back to bite you in the ass later on down the road. Water conditioners like Stress Coat only NEUTRALIZE a few of the bad things in the water, not take out. RODI systems REMOVE pretty much everything.