RDSB results

Okay, I tested nitrates. Nitrates are low...less than 10ppm (maybe < 1ppm...it's hard to tell on my kit - the shades of yellow are very similar). I figure that it's either:

1) a false reading due to the test kit being a few years old *or*
2) that it's an accurate reading because my tank has reached a certain "equilibrium" in the last year when there have been no livestock changes (i.e. algae growth vs. available nitrates from fish waste)

Does option 2 make any sense? I don't know if it works that way or not.

Anyway, I still think I'll setup the RDSB and see if the algae recedes at all. My plan is to take pictures and compare them over time. It may not be very scientific, but it's something I'll use to determine whether to use an RDSB with my new setup. I can post updates regarding the progress if anyone else is interested.

Brian
 
It sounds reasonable, but you might want to get a new test kit and test again to be sure. As long as you are willing to do this, making it as scientific as possible would help. Also, what about testing for the others in the cycle? Nitrite, ammonia, phosphate, etc.. I think it would be very intersting to see what it does to ALL parameters of the tank. Maybe we are missing something focusing on just the nitrates. Perhaps it holds other benefits (or negatives) that contribute to either stability or decline in a closed system.

Worth a try. :fish1:

If I get my butt in gear, I may also try a test as I have a tanbk I have neglected for a while. :(

Good thread if we can keep the chatter down!
 
I installed a RDSB 4 weeks ago on a 220 gal system with 100ppm NO3 measured with a brand new Salifert kit. I used 250 pounds of sand in a 65gal vertical stock tank which gave me a sandbed depth of 9" with 4" of water on top of that. I am feeding it directly from the sump with a Mag 5 with a sponge to help keep detritus out. Pump is throttled down as to not blow the sand around.

I tried a sulfur reactor at the same time but it turned out to be a major headache with no results so I pulled it offline. The only other change i've made was to upgrade my skimmer from a octo nw200 to a reeflo orca 250 (3 days ago) but the nw200 is still running until the 250 is broken in.

As of week 4, no change in NO3.
 
Per recs, the time before results (supposedly due to colonization of bacteria in low oxygen zones) would be 4 week min. And the depth should really be about 11inches or more, at least per A. Calfo.

I set one up two weeks ago, but again, I've been making other changes to the system as well: slowly removing a wet dry, adding flow, adding some xenia, tinkering with my skimmer, etc. So as with so many other setups, no way to make any real conclusions no matter what happens.
 
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What I am thinking of doing is sectioning off part of the sump (maybe 8-10" square) and filling with sand. I would leave the containment area a little lower so that water in that section is deeper than the sand containment area. Doing it this way, I don't need the extra fittings, plumbing and pumps. It will be in a low flow area as to not stir the sand much. Hopefully it will be 12" deep, maybe more. As stated above, I also want to mix in some crushed coral from an old tank to give more pockets in the sand bed. If I could draw I would show you a diagram, but I think you get the idea.

What do you think?
 
I thought the same thing and it would work, but it just does not give you the option of removing/replacing the sand.

Another thought that occured to me: Are any of these kits accurate enough to detect a change of 10ppm over the course of a year?
 
I placed a 6 gallon bucket (Kent Marine Salt Bucket) full of sugar sized sand on my 75 two years ago that is fed by a Maxijet 1200. I had between 20 to 40 ppm nitrates before I added the bucket. 3 months later that number halved and a month after that I had no detectable nitrates.
A year later I upgraded to a 150 gallon tank. When I took the bucket out I removed the first few inches of sand (it looked dirty but the sand beneath was very clean) and replaced it with new. This was in June of 07. This bucket still keeps my trates at or very close to 0. I now have a heavily stocked SPS tank that I feed a LOT daily. I also dose quiet a bit of DT's phytoplankton. I have a refugium but I have not had to trim my Chaeto since August. It just does not grow no matter what I do for it. I have a DAS EX-2 skimmer that performs very well, but I attribute the RDSB to my lack of nitrates. The most I have ever registered on nitrates has been 2ppm but I had not done a water change for a month when I had that reading. My regular maintenance is a 20 gallon water change once or twice a month.
I love my RDSB. Before I had this I honestly thought people who said they had no nitrates were a joke. I had never seen a tank less than 20 ppm prior to this. My SPS are colored up and I get a good growth. The best part are that my fish are very very fat and happy. I do not have to sacrifice feeding them to keep my water clean. They get kelp every day, and I mix 4 different types of frozen foods with phytoplankton and selcon daily. Every now and then I throw in some Formula 1 pellets as a treat as well.
 
<a href=showthread.php?s=&postid=12014983#post12014983 target=_blank>Originally posted</a> by OldmillXxX
What I am thinking of doing is sectioning off part of the sump (maybe 8-10" square) and filling with sand. I would leave the containment area a little lower so that water in that section is deeper than the sand containment area. Doing it this way, I don't need the extra fittings, plumbing and pumps. It will be in a low flow area as to not stir the sand much. Hopefully it will be 12" deep, maybe more. As stated above, I also want to mix in some crushed coral from an old tank to give more pockets in the sand bed. If I could draw I would show you a diagram, but I think you get the idea.

What do you think?

I would not do this the way you are describing. My reason for this is that I know eventually you WILL have to replace the sand in you RDSB. Mine is two years old right now though and I do not plan to change until I notice nitrates begin to raise. If you have a bucket you can plumb a second bucket and run both together in order to seed the second one before removing the old one. Then after a month or so you can pull the old bucket remove the sand and keep the bucket around for when you swap them out again years later. I am worried that if I rip my bucket off the tank I will have a spike in nitrates and my tank is full of sps so I just don't want to have that happen.
If you just have a section of your sump changing out the sand will be much more difficult. Also you will not be able to prefilter the water that much and it will turn into a refugium for sand critters. I also would not add crushed coral I would just go with the Oolitic sugar sand. I have had great results with that.
 
Very good info. I might have missed it, but is the addition of the bucket sand bed the only change you made to your system? It sounds like it was.
 
When it was on the 75 gallon it was the only addition I did. The only addition I had on the 150 when it was setup is the DAS EX2 and a bigger refugium because I have a bigger sump now. Other than that there was no other additions.
 
The bucket setup actually can work great as a fuge if you decide you don't want the RDSB: get rid of most of the sand, cut a hole in the lid and stick a light through it for chaeto, and maybe increase the circulation some. The round walls of the bucket make for great chaeto flow. Of course, you'll lose the "no maintenance" benefit of the RDSB, since other algae can grow and crap can now settle.
 
I installed a RDSB on my system from almost the start. I have a heavily stocked 427gal mixed reef. There are 32 fish, some of them over 6inches long. It's almost 2 years old. Nitrates have never gone over 1.0 that I have ever measured.
 
Have a 30"x12"x15" with 12" of mixed sand. I put a sponge filter 6" in spilting the 2 layers. Flow is around 1000 ltrs per hour, but I have never had zero No3. It's stable around 30ppm and does'nt move.
I think my flow is not right but unsure if too high or low.

I thinking of breaking down and I guess this would confirm if working or night as no3 should rise when i disconnect.
Read alot about these and sure the work but just not in my setup. tank is 250Gal and under fished. With I guess avg LR level.
 
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