DSB concerns

[SkinnyPete]

Wow, I'm posting a lot lately.

Without starting a debate regarding DSB / no DSB (been enough discussion regarding that) - I had a question regarding the known dangers of DSB.

I've got a shallow-ish DSB (about 4") and it was working out fine. Tank has been up for 7 months. After a few months most of my Nassarius snails were killed off by an evil crab or two (since been removed) and the only cleaners left in my tank are hermits and Astrea snails, so I haven't had much sand movement as a result A couple weeks ago, a powerhead fell and blew the sand so badly that I had a huge cloud storm and a hole in my DSB to almost the bottom of the tank. My nitrates were all of a sudden elevated and I lost 2 shrimp (I'm assuming due to elevated nitrates).

Now, first off - my hermits really seem to take a liking to nassarius snails - yes I do have extra shells for them in there. Can I get away with just hermits? They don't seem to mix the sand much though. Any other larger snails that I can get to do the job? Also (and the main purpose for the post) what exactly happens, chemically, when an established deep sand bed is suddenly mixed around like mine? Was the elevated nitrates just a coinc.?

- Skins

 

[greenmaji]

it wasnt a coincidence.. I dont belive in them myself. joke, maybe not a good place for the joke though.. :?
In the low O2 enviroment in the lower levels of your sandbed you are hosting anirobic bacteria that consume NO3, when they were disturbed with O2 enriched water the NO3 they would have been consuming was relised into the tank, that and any that were living there died and that alone could have added more nitrogen to your tank. I hope this helps..

 

[SkinnyPete]

Aaaaaah, makes sense. Thanks. I did a few water changes and got my NO3 down to 25. Doing more water changes and added chaeto so that should help. I was battling PO4 and am finally getting it under control and my hair algae was going away - now its worse than ever.

I guess I should also keep tabs on the suction cups to make sure this doesn't happen again. Two cleaner shrimp - gone. A couple little suction cups sure do cause quite a mess, don't they.

 

[greenmaji]

are you skimming?

 

[SkinnyPete]

I am skimming (Aqua C Remora Pro w/pre skimmer box, probably under-sized for my tank, however no room for sump). Haven't had a real nitrate problem until this cloud storm though. Been about 5ppm. I tested NO3 two days ago and it was above 50. Added chaeto same day and did a 15% wc today and now as I said it's about 25. I'll probably do a 5-10% change every couple days until its down. Got about 25 gallons mixed (110 gallon tank) - which will also help my PO4 (already down to 0.2ppm).

Thanks again.

 

[indy]

I've had my dsb blown to heck and back a couple times without any ill effects. It's about 6" and a couple years old now. But every tank is bound to be a bit different. Too bad about the shrimp. They seem to be the most fragile things in the world, and account for about 90% of every loss I've ever suffered, from a power outage, siphon failure, and the wife's cat running across my power strip and turning it off. Always seems to happen a few weeks after adding a cleaner shrimp...

 

[greenmaji]

I personaly think the skimmer is undersized.. it's barely rated to do your size tank by the manifacture.. that doesnt give any room for error but at least it's the best HOB they make.. If you have a sump I would upgrade to a good sized ASM
how many pounds of LR do you have?
the water changes are whats saving your tank.. good work

 

[SkinnyPete]

I have 170lbs lr, plus a few pounds of rubble in a HOB fuge - I really need to use a signature. I knew going into this that the skimmer would be undersized but I just have no room for a sump in my stand (the tank is 30" tall so not a big footprint).

Keeping the DSB, running open-top and pointing two powerheads towards the surface for gas exchange, adding chaeto, using the preskimmer box, lot of lr, not over-doing the bioload, and doing regular water changes I hope will compensate for my undersized skimmer. That's the plan anyway.

Thanks for all the help.

Skins

 

[greenmaji]

I think BIG sumps are a misnomer.. I think you should have room.. thats just me though. you still have the option of getting a second remora.. or pluming an ASM standalone or getting a standalone skimmer.. I would do a hang on fuge at least.. I wouldnt try to lean on a sandbed.. it will hurt in the end..

 

[SkinnyPete]

I do have a HOB fuge. The only sump I could fit in my stand where a 10gallon or a 20gallon high. Didn't seem worth it. Plus, with the HOB fuge - there really isn't room for a second skimmer. Maybe in the future, with some extra cash I'll figure out my sump issue and build something into the stand - it's just really hard to fit anything through the doors without draining the entire tank.

For now, I'm looking forward to getting home from work today and doing another water change and testing again. Yeah, I guess I'm lucky that I actually enjoy water changes. Or I'm just a little "off".

- Skins

 

[HoopsGuru]

Crank the export back up and I would suggest a detrivore kit over snails alone. The microlife in the sandbed is far more important at keeping things healthy and actually pound for pound turn the bed much more than snails alone digging through it.

While trying to tread around the debate scenario, a DSB is like every other tank. Export and waterflow are still vital the same as bare-bottomed, shallow sandbed, etc. The misnomer was that they were initially thought to be undestructible and people way overfed and didn't pay much attention to the life in the sand. It was only 4 years ago when I set my first up that a national magazine even stated you could not overfeed with a sandbed.....that was the failed misconception, not the sandbed itself.

They have an obvious drawback just like all other systems (ying to the yang I suppose). You get denitrification, but the price is you have to maintain the bed by replacing diversity from time to time.

 

[saltwatersmac]

Hey Skins. I was able to fit a fully modded ASM G3 and a Mag 7 return pump in my 20 gal high sump.

 

[SkinnyPete]

Maybe this is changing the subject and I should start a new thread but just as a quick follow-up - how do I tell if my skimmer is not keeping up with my system? Again, I know it is undersized, but with a deep sand bed and tons of rock displacing water - I was hoping it would be okay. Do I just watching nitrate levels and if they are low, I'm okay? Would I be getting really dark skimate meaning that there is tons of junk to pull out but it just can't get it all? Because my skimate isn't very dark...it's like green tea. And my levels seem okay, but I do religious small water changes so that may be why? Just curious what the warning signs would be.

- Skins

 

[HoopsGuru]

If I had a DSB and a skimmer, I would not expect any nitrate levels at all...that would be my firstindicator that I needed to analyze my system (overfeeding, overstocking, under export, etc.).

As for the color of the skimmate, it unfortunately comes down to the efficiency of the skimmer at times. Even in a skanky tank, some models/brands will only pull tea colored skimmate due to various reasons....pump size, air/water contact time, etc. What skimmer do you use?

 

[SkinnyPete]

I'm using the Remora Pro with Mag(3?) and recently added preskimmer box. It definitely works better with the preskimmer box. I think my nitrates before this cloud storm was due to overfeeding. I was feeding home made blender mush daily, plus nori for my tang daily. I've been doing saltwater for a while, but mostly predator tanks. Always fed my predator tank once every couple-few days, but didn't think it would apply to community tanks. Basically, I don't know how my tank reacts if I'm doing things correctly It may have been my fault - not my skimmer. So, I'll keep an eye on the system now that I've cut back feeding and added the preskimmer.

Is this a schizophrenic thread or what?

 

[Royal Gramma]

EDIT: nm, missed the whole 2d page of posts

 

[greenmaji]

The AquaC remora pro (the mag 3 makes it a pro pretty much) with the pre skimming box is the best HOB setup IMO. A 110gallon tank is going to be its upper limits IMO.. It should be able to do the job if everything else is up to par.

 

[HoopsGuru]

Most reef fish (if not all, other than predators) eat many times throughout the day and really should be fed at least daily in our aquariums. If you have a skimmer and a DSB and not wildly overstocked, your tank should be able to handle this pretty well. If not (nuisance algae, etc.) I would analyze the amount you are feeding, etc. as a most likely cause or consider having to jump up to a larger skimmer or large DIY model if you are crafty.