so frustrated with my 7 year old tank

[CTurtleGirl]

I've been into reefing for about 8 years now. I had a beautiful 75 gallon reef tank with corals, clams, etc. I had no problems except a little turf algae problem that I kept at bay with manual pulling. Then 2 1/2 years ago we moved and everything changed. The corals started dying, my anemone that we had had for 7 years suffered and finally died about 3 months ago. The brown slime algae, (not sure what kind it is), coats everything the day after I scrape it away. We are down to 3 corals that are still alive. We haven't had any problems with fish deaths. I cannot get the nitrates down. They are running about 30. All other paramaters are just fine. I bought an ro/di filter a couple months ago thinking that might help even though our tap water tested with a TDS meter at only 25. This change hasn't done any good. Since the filter I have been changing out 25 gallons every two weeks and nothing has gotten better, it has gotten worse with the algae. This tank is about 7 years old now. I am suspicious of the sand bed causing the problems but I am not sure how to tell if that is the culprit. Here are all specs:

75 gallon acrylic tank with overflow
20 gallon sump
turboflotor skimmer with oceanrunner pump upgrade
4 maxi jet powerheads on a wavemaster pro
2 175 watt 12k MH on 10 hour day cycle
75 lbs live rock
3-4 inch deep sandbed
one mated pair of false percula
one sixline wrasse
one lawnmower blenny
2 frogspawn corals
1 hydnophora
various crabs, snails, 2 starfish
ca 400
ammonia 0 /nitrite 0/ nitrate 30*(problem area)
ph 8.2
phosphate 0
alkalinity 8dkh

Any thoughts on to what the problem could be? I feed twice a day of either flake or strained brine shrimp so I don't think over feeding is a problem. I've read something on this board about old deep sand beds leaching out nitrates. I'm wondering if that is my problem and how to tell if it is.

Thanks for any help

CTG

 

[Len]

You seem to be doing things fine now, so it very well be accumulated nutrients in your sandbed that built up over the years (especially when you weren't using RO). I had a sandbed for nearly 10 years with no problem, but some people report problems after a few years. Have you ever siphoned your sandbed in all this time? Removing/replacing your sandbed might be what your tank needs. I know many people who who have done this and reported good results.

 

[CTurtleGirl]

To be honest, I have never siphoned my sandbed. I always thought that it would remove the good bacteria or potentially damage inverts living in the sandbed like starfish and certain snails. At this point would it be detrimental to start siphoning? Should I remove all the rock and siphon or just the areas I can access now. And by siphon do you mean with the python all the way to the bottom of the sandbed or just the top layer. I have freshwater tanks that I siphon with the python and I go all the way to the bottom but obviously different media (gravel instead of sand). Thanks!

CTG

 

[S!mon]

My tank is four years old and I am haveing the same problem. I changed my sand bed out about a year ago and nothing changed. A guy at a LFS thinks it may have something to do with temp changes throught day\night, but I don't see how this could be. Try to post a pic of your tank, I've seen several people on this forum with the same problem.

 

[Len]

I siphon my sandbed portions at a time. For example, I'll siphon half with one water change, then the other half with the next water change. This helps the sandbed repopulate itself. I siphon all the way to the bottom, or as far as it will go into the sand. I only siphon the portion I can get access too. There is an incredible amount of detritus that will come out the first few siphons. I'd get some extra mechanical filtration on the tank during this time, removing it a few days after the tank has cleared up.

 

[Anonymous]

I've read something on this board about old deep sand beds leaching out nitrates. I'm wondering if that is my problem and how to tell if it is.

CTG

This is what I would think.

Have you turned your protein skimme rup a bit? Run it very wet. This will result in a bit more water change, but may be helpful.

As well, test for copper maybe? If you were using a tap water before, copper could have been absorbed into the rock. Live rock is very good at absorbing copper. Disturbing the rock may have released it.

 

[CTurtleGirl]

I do not have any current pics of the tank since my digital cam does not work anymore. I talked with someone at the local saltwater fish store and they said I should remove the sand bed because if I siphon it will release toxic sulfur and other toxins into the water potentially harming my livestock. Also if I were to remove the DSB, what is the safest way to do so. I had a procedure in mind wich involved removing livestock to a seperate tank while the process was done. What do you guys think?

Thanks,

CTG

 

[Len]

Nah, that sulfur concern is really overblown. In fact, I can't recall a single person reporting death by sulfur poisoning. Removing the sandbed would release this same sulfur into the water, so the LFS' position isn't very rational to me.

However, I can see removing it as a possible remedy. I've never removed entire sandbeds before. I know Thales has though .... I'll try to get him to chime in

 

[Anonymous]

I've removed whole sand beds with out any problems. Mainly when moving tanks. I just siphon half the water out to save, and use the rest to do the sand bed.

It's hydrogen sulfide you smell, not sulfur.

 

[CTurtleGirl]

Thanks for the replies. I think I am definitley going to remove the sandbed. I will siphon out half the water to save and put back in. Keep the top 1/2 inch of sand to just cover the bottom when done and remove the rest. I will put all livestock in a spare tank with tank water to keep them out of the way and take out all live rock into spare buckets of tank water. When everything is put back in there will essentially be at least a 50 percent water change. Should I be able to just put all the livestock back in or should I wait a while for any spikes?

CTG

 

[Len]

That's how most people do it, and while some say there's a little spike, most say everything goes through the process unphased.

 

[Anonymous]

That's about when I had to redo my tank.

 

[S!mon]

So remove the sand bed and let the tank go through what ever spike it may encounter and then and put back new sand?

 

[Len]

If you keep the rock submerged during most of the transfer, I don't think you'll experience too harsh a spike.

 

[pcardone]

If you are producing nitrates and doing water changes. then I feel that you have a pocket somwhere that the bad bacteria is doing its job. Mine was in the sand bed yours can be in an area that getting poor water flow. move your power heads around, see if any rocks let off alot of debris. They say you have to be careful removing sand beds because they have toxic stuff to. Maybe you stirred up some of the bad stuff in the move and now you have to wait it out. keep looking till you find the solution to the problem.

 

[Anonymous]

:? I really think before you go through the incredible expense and time to change over an entire bed, you look into some other possible causes.

Test your copper
Turn the skimmer up
Do a more frequent water change
Cut the feeding back a little (twice a day is too much, IMO)
Test other parameters

Brown slime, I am pretty sure, is because of a poor water source? Your mention of a lot of hair algae lends me to this direction as well.

As well, what is your salinity/sg?

Have you tested magnesium? Do you have good coraline growth?

I think there may be more here than just ripping out a bed.

 

[Anonymous]

Start a new tank. Seriously.

 

[S!mon]

I have been using RO\DI for 8 months now doing 10 gallon weekly changes on a 30 gallon tank. Coraline growth has all but stopped. I don't have my test results in front of me, but I will list them as best I can
NO3 0.2ppm
PO4 undetectable
pH 7.8-8.1
cal. 430
sp gr. 1.024
temp. 75-78'F

 

[Anonymous]

I have siphoned a sand bed out, it works pretty well if you want to remove it. Just take out some with each water change.

We removed an old DSB gone bad after battling algae for a long time, despite new MH bulbs, twice weekly (at least) water change where handfuls of hair algae were taken out, copper testing, new upgraded RO unit, better flow, daily kalk drips, new expensive skimmer, and such reduced feeding that I almost killed one of my tangs from starvation.


Note that once the sandbed was out, the rocks were "shedding" detritus for a long time, and it took a good while to see the end of the hair algae. I think it was just years of junk buildup in the system and thus the rocks.

When you first set up a DSB, it works great, so I developed this attitude that it could handle all the nutrients going into it. But I found that they are not a black hole, sending all the fish poo to another side of the universe. All that stuff is still in your tank, building up.

That experience changed how I feel about reefs. I sure did loose a lot of corals in that lesson. I truly think you have to keep it clean, and not rely on biologic fitration to process the poo and other organic matter.

I have a tank now that is fish and anemone focused, and it does have a sandbed. This time around I am vacuuming out sections when I do a water change. I still see worms and such, they just multiply and move into the vacuumed section.

 

[Anonymous]

Hmmm...I am wondering if anyone has in info on whether people have had crashes with crushed coral substrate.

In al of the years, I never had one crash using cc, but I seem to read a lot about sb's crashing and having to start over...

ANyone else have any input? SHould I sta

Should I start a thread? Yes...I shall.