Live sand bed & nitrate

[neptune]

Would like some advice please.

I have a 48 gallon FOWLR + inverts (and some mushrooms). Power compacts / coralife skimmer / powerhead / hob filter to pull out detritus / fish: Mandarin / bluehead goby / 2 percula clowns / shrimp / 25+ hermits / 15snails / 50 pounds live rock / 9 years old - last year I had a die off as a result of the ice storm I don' think since that disaster my sand bed has recovered?

My tank has high nitrates 50+ after multiple water changes it keeps reading 50+. I have had this confirmed from LFS and I just purchased a new test kit. From this forum I now understand the problem is (old tank syndrome) and that the nitrates are in my live (dead) sand bed. As I do water changes I am syphoning my sand bed. The net effect is that I must be releasing the nitrates trapped in the sand bed into the water column and I am not reducing my nitrates. I am syphoning slowly and pinching the hose as I read from this forum it should help?

Other then the test kit showing 50+ nitrates my tank looks fantastic. Coraline algae growing / mushroom doing fine / fish so happy / I do have red algae on the skimmer pump and back wall. I am leaving some of the algae grow b/c I think this will eat/reduce the nitrate? I do not have a sump.

A few questions: How do I reduce my nitrates? Do I assume I already took out most of my nitrates and do one more massive water change? Once I clean my sand will it become alive again? I purchased 40 pounds of live sand bahama oolite years ago. I just added a bag of the same 2 weeks ago to reseed my bed? Can I fix this with water changes and vacumming the sand?

OR do I need to pull out my sand bed entirely and start over? I really do not want this option....

If I swap and replace the sand advantages of using live sand vs home depot vs macro - I read some old threads. Why is the macro sand so much better? I don't get it?

Nice to meet everyone.. once this tank gets humming again I am going to set up a 90 gallon with sump - slowly. Just want to stabalise for my goby and mandarin. I cant tell you how much I love my goby!! He needs the sand bed or I at this point I would go glass bottom. FRUSTRATED with the nitrate issue.

suggestions?

 

[frank180reef]

welcome, there are a bunch of other members fighting the nitrates

do you have a refugium?

how old is ur tank?
welcome aboard

Frank

 

[Cjtabares]

I think he said it was 9 years old with no refugium

 

[neptune]

Do I gravel vacuum or do I need to pull out all of the old sand? Suggestions?

 

[Muddskipper35]

Curiously you didnt mention your feeding schedule and what your feeding..

This is My Opinion below some will disagree...........
While I do believe in old tank syndrome I dont believe a sand bed will stop processing nitrates nor do I believe a tank will reach a point at which it will no longer process nitrates through a DSB if properly maintained through partial bed changes every couple yrs. If this were true then would not all the oceans be high in nitrates? Just my thoughts. I am a firm believer in changing out parts of the sand bed slowly and periodically due to detrius buildup below the top 1 or 2 inches to keep from compacting the bed and stopping total water exchange, or at least creating a large dead spot within.

A reading of 50 seems high to me even if you didnt have a sand bed. Are you having algea problems as well? can you post a pic of the tank?

 

[JohnK]

If your siphioning the sand bed (gravel vac-ing it, not removing it, right?) that may be part of the problem.

The reason a DSB keeps nitrate down is that an anoxic and or anerobic condition occurs and this allows the growth of denitrifying bacteria in the depths of the sand.

If you disrupt the sand, you mix it and likely knock back the denitrifying bacteria quite a bit.

IMO/IME what does go bad with DSB's over time is that some detritis or whatever does get mixed in and eventually you get a lingering phosphate level that doesn't seem to go away. If your fighting nitrate issues, IMO, siphioning the sand does not make sense as the disruption will serve to make the sand LESS able to process nitrate, while removing what might be causing phosphate issues. Siphioning the sand might be good to fight phosphate, but not nitrate.

Does this make sense?


Is your sand fine sand, or course sand, or crushed coral?

 

[Arthur1]

How deep is your sand bed?

 

[Kenny B]

How often are you servicing the HOB filter? Is much food entering the HOB. If so, and your not rinsing the filter after you feed, the nitrate could be from the HOB, especially if you feed heavy and often. The water forced through it forces a rapid breakdown of the trapped organic compounds. I don't see mention of a protien skimmer either. I would recommend getting a good one.

 

[neptune]

So I think I was overfeeding a tad... b/c I had a new mandarin and blue spotted goby and wanted to ensure they settled in correctly. Now I am feeding one cube of food every other day. My livestock is listed above. I am switching between brine shrimp and formula 1 cubes. I have so many hermit crabs/ snails that I think I must offer them a tad more then the live rock that is totally wiped clean.

I am going to do a massive water change tomorrow. I am 50+ Nitrates and a 48 gallon tank. If I do 20 gallons I must make a huge dent into this? I am starting to make the saltwater now. Do I vacuum my live (dead) sand or not? If I do not get rid of my nitrate I can't get my new fish and am exhausted with all the water changes.

***I am also going to rinse my HOB coralife skimmer by soaking in vinegar tonight. It has in the past pulled out more GUNK so I think this might contribute to the problem.

I am pondering the phosphate point re: the DSB. But that still makes me think I need to vacuum my sand bed b/c ultimately I need the gunk out of the sand bed.
I will post a photo now also.


vote / share how you care for your sand bed? and send links where I can read more about this?

thank you!!

 

[neptune]

Photo of tank with High nitrates...

Photo of tanks 50+ nitrate...

 

[frank180reef]

great looking tank btw
My guess is the nitates should drop by the amount of water u change...likely to around 30-35 ppm

So my sand bed was 5 yo, I moved it and it has been at my new house for 7-8 years now. I dont really do anything to it

Frank

 

[skotty52]

I went through a very similar problem with a 4-5 year old tank. I also went through the "well I guess I'll do another water change" thing. After awhile I began to realize that water changes were only fixing the problem temporarily and the nitrates were back up very quickly. Later when I took the tank down, I found out that the oolithic sand in my sump was about as hard as a rock, no way water could be getting into the anerobic layer. I agree with the above that simply stirring up the sand is not a solution. In my new system, I have added a 37 gallon trash can sump in addition to my regular sump (great if you have the room). In the sump is alot of macroalgae, plus I have stacked tupper ware containers (about 17x6x7) crosswise one on top of the other. Each one has about 4 inches of oolithic sand. After about a month my nitrates are at 0. The idea with the containers is, over time, to replace or stir the sand in each on a staggered basis. In this way, I will always have DSB capability, but will be able to re-invigorate each "mini-DSB" in rotation. This means I won't have to be digging out a bunch of sand from a tank, disrupting everything else in the process, including nearby DSB areas (alot neater to fix/stir/replace the sand outside of the tank as well). I would be curious to hear anyone's thoughts on this approach. I am just making it up as I go, but seems to make sense.

 

[jayman10134]

I went through a very similar problem with a 4-5 year old tank. I also went through the "well I guess I'll do another water change" thing. After awhile I began to realize that water changes were only fixing the problem temporarily and the nitrates were back up very quickly. Later when I took the tank down, I found out that the oolithic sand in my sump was about as hard as a rock, no way water could be getting into the anerobic layer. I agree with the above that simply stirring up the sand is not a solution. In my new system, I have added a 37 gallon trash can sump in addition to my regular sump (great if you have the room). In the sump is alot of macroalgae, plus I have stacked tupper ware containers (about 17x6x7) crosswise one on top of the other. Each one has about 4 inches of oolithic sand. After about a month my nitrates are at 0. The idea with the containers is, over time, to replace or stir the sand in each on a staggered basis. In this way, I will always have DSB capability, but will be able to re-invigorate each "mini-DSB" in rotation. This means I won't have to be digging out a bunch of sand from a tank, disrupting everything else in the process, including nearby DSB areas (alot neater to fix/stir/replace the sand outside of the tank as well). I would be curious to hear anyone's thoughts on this approach. I am just making it up as I go, but seems to make sense.

that is an amazing idea. so in your tank do you just have a thin layer of sand, not deep enough to qualify as a DSB?