Deep sand bed
 

Is deep sand bed sump/ refugium beneficial if i am already using NP-Bio pellets?? :biggrin:
Comments and suggestions will be so much appreciated!!!

thanks,
tedy

It depends on what you consider beneficial.

You could either have a display sand bed that needs to be cleaned regularly.
That way you could have any grain size you want, any depth you want and keep any animals you would like.
That kind of sand bed needs to be cleaned by you.

You could have a properly set up and functioning sand bed, intended to process any detritus that falls on it. (within limits!) A heavy bio load can overwhelm it.
That way you need specific grain size, at least 4 inches in depth, no crabs, shrimp, sandsifting gobies, sand dollars, sand sifting starfish or any other animals that sift or move sand. They will essentially eat all the bethnic infauna that keep the sand moving properly.

Either sand bed will still help with denitrification.

thanks for the quick response Mitch. I missed something on my question, it is going to be for my sump/refugium that i am planning to put up not for display..:lol:

thanks

I would treat it as a display sandbed then.
Your sump is too small for a fully functional dsb.
It still will help with denitrification.

Personally, I don't think there is a reason to have a DSB this day and age. We have many other options available, and have learned a lot in the hobby since the days that DSB were standard. Imo, DSB are too fussy, too easy to do improperly, and may or may not crash even when it seems they are done properly.

I'm also not a fan of these Bio-Pellets. I haven't tried them myself, but it seems the success rate is 50/50 which I don't think is good enough, especially when there are alternatives that have a better success rate. Everyone's looking for a quick fix though, and this makes the Bio-Pellets an easy sell.

Denitrification should be handled by your live rock. If you're getting a build up of nitrate you need to look for the source. The source can usually be found from over-stocking (and/or over-feeding), poor maintenance (and/or insufficient skimmer), and/or poor circulation. The source of nitrate is always organic breakdown. The purpose of a protein skimmer is to remove organics before they have a chance to breakdown. The purpose of powerheads is to keep organics suspended in the water column so they make it to the skimmer. Settled detritus results in organic breakdown.

Instead of using a refugium and/or DSB (in tank or refugium) I would suggest the use of a chaeto chamber in the sump instead. Provide a large chamber in the sump, provide intense low Kelvin lighting, stock it with a ball of chaeto, add a powerhead to keep the ball rolling (literally), and keep the ball trimmed so it is always freely rolling, and this method will absorb an astounding amount of nitrate and phosphate. The catch is keeping the ball rolling. Most people don't do it right, but if done properly it is quite impressive.

There is a line where over-stocking becomes the problem. No matter how much circulation you provide, no matter how much chaeto you can grow, you just can't stay ahead of nitrate. You may not be over-stocking the tank, but you may be over-stocking the protein skimmer. Lots of fish means lots of waste. Lots of waste means you need an efficient skimmer to remove this waste. If you have done everything else I have mentioned and you still struggle, take a look at your skimmer, maybe you need a bigger (or better) skimmer to keep up to the bioload you are putting on it. Or less fish. :p

I started running bio pellets on my 77 just before christmas.My nitrate levels were not too bad, but phosphates were fairly high.( I use tap water treated with prime for top off and WC's)I had alot of HA and a cyano problem.Just checked my tank parameters a couple days ago, and my phos and nitrate are at undetectable levels.HA is only on 1 rock now and cyano is gone.(I did cut back on lighting for a couple weeks to help)
I give the pellets 2 thunbs up... so far :)

I just use LR rubble in my sump

thanks a lot!! that's why i decided to ask it here first before doing some changes on my sump. so far i don't really have a big issue (bad) with my tank when it comes to water parameters..:lol:

thanks,
teddy

You defineately will have.
You have four fast growing tangs in a 75 gallon tank.
You should plan now to set up a minimum six foot tank. I don't think that anyone will disagree with this advice.

I have a DSB in the tank. Downside is that it limits the amount of flow you can put in the tank. Anymore than I presently have (~ 7000 usgph), then I'd have a sand storm. The bed is shallowest at the centre of the tank at a couple of inches and at the edges it's close to 8 inches at some points. I personally like the aesthetics of a DSB in the DT. The flow I do have is adequate for the corals. I don't care about detritus transport to the sump. It can settle in calm areas of the DT where the DSB is deep. It gets processed by all the benthic fauna in the DSB. I find that BB tanks look sterile and unnatural. Shallow sand beds and BB tanks have the maintenance headache of constantly vacuuming detritus.

Let me mention that I also have:
- a lot of live rock,
- bio-pellets,
- a good skimmer
- a fuge with chaeto.
- run activated carbon (Rox 0.8 from BRS)
- run HC GFO (also from BRS)

Seems to me that all this is needed to keep nutrients at levels low enough to have healthy SPS corals (nitrates 0 and PO4 at 0.05 ppm). I think the biggest contributor in keeping P low is the GFO, with assistance from the chaeto fuge. Activated carbon keeps my water from going yellow. I don't know if the corals are negatively affected by yellow water, except for the loss of PAR as the yellow components absorb light in the UV/blue spectrum. I don't have a clue if my bio-pellets are helping. All the aforementioned are back-up to my primary filtration from the live rock/skimmer/DSB, without which I don't think my system would function at all. So, I think a multi-pronged approach is needed.

I like sandbeds just for the extra critters it provides home for. I believe our tanks, just like any ecosystem should be built on the pyramid system.....large numbers of algae/bacteria, smaller numbers of critters that eat the algae/bacteria and fewer yet critters that eat them. Not easy to do when you have limited space and want to have things that you can see :lol: