Help with cloudy water in my nano tank

[BrettDS]

I've got an 8G nano reef and I've been struggling with cloudy water in the tank for quite a while now. The tank has no fish and actually functions as an invert quarantine tank for my display tank, but I leave it up all the time and it has a few long term invert residents.

It's been cloudy for several months now and I keep thinking that it will naturally go away with time, but it doesn't seem to be doing that. The water is more milky than green, so I don't think it's an algae bloom. Nutrients are kept very low, so I can't imagine that an algae or bacteria bloom would even be fed enough to keep going for several months. I only feed about 3-4 tiny pellets once every 2-3 days.

The tank has no skimmer or mechanical filtration. It's got about 6lbs of live rock (that started as dry rock) and about an inch of fine sand. It's also got a CurrentUSA wave pump as well as the AIO filter pump to provide water circulation. It has two CurrentUSA Pro LED light strips to light the tank, so it gets a good amount of light.

I am using the AutoAqua Smart AWC for ATO and auto water change. It's set to automatically change about 1.5 cups of water every 18 hours, so while there is no skimmer or mechanical filtration the water should be kept pretty clean.

Water parameters look good to me, but here they are:
pH: 8.5 (API Test Strip)
Ammonia: 0ppm (API)
Nitrate: 0ppm (Salifert)
Magnesium: 1200ppm (Salifert)
Phosphate: 0.02ppm (Hanna Phosphorus ULR)
Alkalinity: 10.5dkh (Hanna)
Calcium: 465ppm (Hanna)

Other than keeping up with water changes and giving it time I've tried the following:

I put a small submersible filter in the tank with a small piece of a filter sock in it to provide some mechanical filtration for about two weeks. I changed out the filter sock material several times while it was in there and while it did get stained brown it didn't make a difference at all in terms of water cloudiness. I have since removed it.

The bio load is pretty light, but I was afraid that the small amount of rock might not be enough surface area for the beneficial bacteria, so about a week ago I added 3.2oz of Marine Pure "˜gems' to the filtration area, but it doesn't seem to have made a difference. The water is still as cloudy as ever.

Any thoughts on what I'm missing or what else I could try?

 

[rfgonzo]

Try cutting back on the 3 or 4 pellets to once a week or less, 8gal is small. You may be feeding to much. Run some activated carbon to help absorb nutrients that feed bacteria bloom. Are you using RO/DI for topoff and water changes?

 

[BrettDS]

Thanks for the reply. I am using RODI water in the tank. I feel like if I was over feeding it would show up in the phosphate and nitrate readings, but maybe it's all bound in a bacterial bloom. I'll cut back on feeding and see if that helps. I'll also run some carbon and see if that helps as well.

 

[jlmawp]

Off topic, what is that yellow fella you have on the glass?

 

[RioReefr]

This is what I think -- I notice a few upside-down snails (trochus?)....perhaps they are dead and decaying. Hence the source of the crappy water quality.
Check all your inverts and see if they are still alive, if not then toss them out. Check inside the rockwork too, snails can get stuck in a hole and just die.

Pick up some small packets of Seachem GAC (or other GAC) and Purigen. Minimal cost.

 

[BrettDS]

This is what I think -- I notice a few upside-down snails (trochus?)....perhaps they are dead and decaying. Hence the source of the crappy water quality.
Check all your inverts and see if they are still alive, if not then toss them out. Check inside the rockwork too, snails can get stuck in a hole and just die.

Pick up some small packets of Seachem GAC (or other GAC) and Purigen. Minimal cost.

Hmm, you might be on to something, although I'm not sure. Like I said, this is also an invert Q tank for my 220G tank and I've quarantined several batches of snails for the big tank and not all of them made it. I just left the shells in the Q tank. I think the newest shells are still several months old though as I haven't really been adding anything to the tank while I figure out the cloudiness issue.

I assumed that any rotting snail bits would have been long gone, but I'm willing to try anything at this point, so I went ahead and pulled the shells out. I was a bit surprised that there was a bit of an odor from some of the shells. Nothing too noxious and overpowering, but still noticeable, so there may have still been something decomposing there causing water quality issues.

I've gotta admit that I've always had bigger tanks and a few dead snails wouldn't be an issue in my 220G tank, so I'm used to just letting nature take its course. But I guess things are different with only 8 gallons and I need to be a little more careful.

In any case, the shells are out now and I already had some ROX carbon for my big tank, so I put a bit of that into a small filter in the 8 gallon tank and maybe that will help clear it up. I'll let you know how it looks in a few days.

 

[BrettDS]

Just to follow up on this, I've been running carbon for 5 days now and I still don't see any improvement in water cloudiness. I've only fed once during that 5 day period and that was literally 4 tiny 1mm pellets two days ago.

I didn't have any purigen, but I ordered some and when that gets here on Sunday I'll switch out the carbon for the purigen.

If anyone else has any thoughts in the mean time I'd be happy to hear them

Thanks much

 

[manateemark]

I would ask whether you rinsed the sand before starting the tank or not? If not then perhaps it's just very fine silt floating in the water column. I just started another tank and used Special Grade Aragonite and it took about an hour of rinsing with water in order for all of the silt to come out. If that is the case then you can probably just remove the rock from your tank, drain it, rinse, and then put the rocks back in and fill it up. It would slightly hurt the "cycle" on the tank, but since it's an invert QT tank then it perhaps is not too far along anyways.

 

[BrettDS]

I would ask whether you rinsed the sand before starting the tank or not? If not then perhaps it's just very fine silt floating in the water column. I just started another tank and used Special Grade Aragonite and it took about an hour of rinsing with water in order for all of the silt to come out. If that is the case then you can probably just remove the rock from your tank, drain it, rinse, and then put the rocks back in and fill it up. It would slightly hurt the "cycle" on the tank, but since it's an invert QT tank then it perhaps is not too far along anyways.

Thanks for the reply, but I'm pretty sure it's not that. The tank has been up with the sand in it for 5 or 6 months now. I think any fines would have settled down by now and/or gotten removed through water changes.

 

[manateemark]

Thanks for the reply, but I'm pretty sure it's not that. The tank has been up with the sand in it for 5 or 6 months now. I think any fines would have settled down by now and/or gotten removed through water changes.

Have you tried doing a couple of large (80-90%) water changes?Aso what salt are you using?

 

[BrettDS]

Have you tried doing a couple of large (80-90%) water changes?Aso what salt are you using?

I haven't tried any huge water changes like that, but I have done some bigger ones... maybe 30 or 40%.

I'm using instant ocean salt, the same that I'm using in my big tank with no issues.

 

[manateemark]

Since you're using instant ocean salt and it only costs $38 for a 200 box of that salt I would say just go ahead and 2 90% water changes and see if that fixes the solution. A 30% and 40% water change will still leave 42% of the original water in the tank. 2 90% water changes will only leave 1% of the original water in the tank. The water changes are only going to cost a total of $2.77, so I'd say that's the cheapest way to figure out if it's just cloudy water. If it comes back then we know it's something else.

When you're refilling the tank use a rock or something to pour the water onto as to not disturb the sand bed, as that's still what I think is contributing to the water cloudiness.

 

[wrott]

You could try putting filter-floss (glasswool) in the filter. This usually clears the water an a few hrs.

 

[BrettDS]

Since you're using instant ocean salt and it only costs $38 for a 200 box of that salt I would say just go ahead and 2 90% water changes and see if that fixes the solution. A 30% and 40% water change will still leave 42% of the original water in the tank. 2 90% water changes will only leave 1% of the original water in the tank. The water changes are only going to cost a total of $2.77, so I'd say that's the cheapest way to figure out if it's just cloudy water. If it comes back then we know it's something else.

When you're refilling the tank use a rock or something to pour the water onto as to not disturb the sand bed, as that's still what I think is contributing to the water cloudiness.

It's not really the cost that concerns me, but rather the shock of a big water change on the few inhabitants of the tank. At this point the purigen should arrive tomorrow so I think I'll try that first. If the water is still cloudy in a week or so I'll go ahead with a couple of 90% water changes.

 

[manateemark]

It's not really the cost that concerns me, but rather the shock of a big water change on the few inhabitants of the tank. At this point the purigen should arrive tomorrow so I think I'll try that first. If the water is still cloudy in a week or so I'll go ahead with a couple of 90% water changes.

What are all of the inhabitants in the tank?

 

[BrettDS]

What are all of the inhabitants in the tank?

One blood red fire shrimp, one small (1 inch) yellow cucumber, and one 2 inch conch.

 

[manateemark]

They will be 100% fine with a large water change like an 80 or 90%. The bacteria is found in the rocks and sand, not really the water.

 

[BrettDS]

They will be 100% fine with a large water change like an 80 or 90%. The bacteria is found in the rocks and sand, not really the water.

It's not the bacteria that I'm concerned about, but any salinity, temp, or pH changes could be a shock to them. I do agree that it wouldn't likely be a problem and obviously I can take time to ensure that everything matches as much as possible, but if the purigen can take care of it without the water change then all the better.

It's been cloudy for a long time now and it doesn't seem to be hurting anything (other than making it annoying to look at) so I don't really feel a need to rush things. I think a large water change is a valid diagnostic step and I'll definitely try it if I get nowhere with the purigen.

I very much appreciate your ideas here and hopefully I can get clear water soon

 

[Fourstars]

Large water changes are no problem since you have control of temp, salinity, and PH. If you don’t, then you have been doing your water changes incorrectly.

 

[manateemark]

Large water changes are no problem since you have control of temp, salinity, and PH. If you don't, then you have been doing your water changes incorrectly.

I agree with this completely. You can control all of those parameters that you're concerned with. Just match the temp with a heater, salinity with a refractometer, and then the ph using a ph buffer because the alkalinity of the tank won't matter in this scenario.