Too Much biomedia???

[Pntbll687]

So I've been battling some diatoms and a little bit of algae on my sandbed for a couple months, 180g tank with eshopps RS-300 sump, I ballpark the total volume to be around 200g. I've adjusted flow every which way, I've siphoned the sand multiple times, but it always came back in a day or two. My nitrates kept rising into the 30-40 range, even with minimal feeding (every other or every 2 days) and weekly 30g water changes.

Now I had used seachem matrix (about 6 liters worth) from my old tank when I transferred everything to the new tank, I thought maybe it's trapping detritus and causing issues. I took all of the matrix out, and rinsed it in tank water during the water change. There wasn't as much detritus as i thought there would be. There was some, but not enough to make me think that was the issue.

Well anyway, I decided to keep the matrix out of the sump and see how things go. Now it's been about two months and I can report that the algae and diatoms are far LESS than before. It takes about 6 days to even be noticeable after water changes. The nitrates also don't rise as fast, and hover in the 15-20ppm range if i need to push off a water change a day or two.

I'm pretty much just rambling now and wondering if the 100,000sqft of surface area we all have been sold on for biomedia is even necessary?

 

[piranhaman00]

Taking out the matrix wouldnt cause your nitrates to lower, it must have been the washing off of detritus or another factor.

IMO you cannot have too much biofiltration, I prefer to have my nutrients bottom out and dose to keep them above zero, this way I have total control.

 

[Malifry97]

Taking out the matrix wouldnt cause your nitrates to lower, it must have been the washing off of detritus or another factor.

IMO you cannot have too much biofiltration, I prefer to have my nutrients bottom out and dose to keep them above zero, this way I have total control.

I think what he is saying is that all the surface area may have just been a detritus holder. If this is the case, then yes, removing the matrix could cause the nitrates to lower.

 

[SPR1968]

I think there may be so many variables, it could even be that the bio filtration systems in the rocks etc has increased as the tank matures and develops. Assuming it’s a relatively new from what you’ve said.

if your getting diatoms I would initially make sure your using 0 TDS water for changes, and it may be worth looking into if silicates are being introduced somewhere, from the water for example to feed the diatoms.

Filtration media is sort of self limiting, and as said above you can’t really have to much

 

[piranhaman00]

I think what he is saying is that all the surface area may have just been a detritus holder. If this is the case, then yes, removing the matrix could cause the nitrates to lower.

Oh I see, yes I guess having too much of anything in your sump could create a place for detritus to settle.

 

[Pntbll687]

I think what he is saying is that all the surface area may have just been a detritus holder.

More along the lines of just because you have 100,000sqft of media are you using all that media?

 

[piranhaman00]

More along the lines of just because you have 100,000sqft of media are you using all that media?

If your nutrients are above zero there is room for more biofiltration! This doesnt have to be matrix ect. how much rock do you have?

 

[Pntbll687]

If your nutrients are above zero there is room for more biofiltration! This doesnt have to be matrix ect. how much rock do you have?

Don't know exactly, probably between 120-150lbs and 100lbs of sand

 

[piranhaman00]

Don't know exactly, probably between 120-150lbs and 100lbs of sand

Thats a lot! Someone else mentioned the age of the aquarium, that is a great point. It could be coincidental that taking out the matrix coincided with bacterial maturity? Im not sure, lots of factors.

 

[45ZoaGarden]

You cannot have too much boo filtration. But I do think filtration is your problem. Are you using rodi water? How old are the membranes? Are you getting 0tds? Do you have a skimmer? Running a fuge with cheato? How much live rock do you have? Did you get it as dry rock? And finally what test kit are you using?

 

[Malifry97]

More along the lines of just because you have 100,000sqft of media are you using all that media?

No you may not be depending on how much ammonia is produced. There is only enough bacteria for the amount of food produced.

 

[Malifry97]

But I agree that the matrix is not the root of the problem

 

[Pntbll687]

You cannot have too much boo filtration. But I do think filtration is your problem. Are you using rodi water? How old are the membranes? Are you getting 0tds? Do you have a skimmer? Running a fuge with cheato? How much live rock do you have? Did you get it as dry rock? And finally what test kit are you using?

Yes I'm using rodi water, 0tds after di. The unit is maybe a year old.

Skimmer is an eshopps x-220

Not running a fuge

Some of the rock was bought as live rock, some was dry rock. All rock is over 4+ years old, minus a couple of smaller pieces that may be about a year in use.

All the livestock and rock was transferred from a DeepSea aquatics 190 that I had set up for 3 years, and a couple of smaller tanks before that. I did rinse and add new sand. I'm thinking the sand may have had some silicates still in it and that's where I'm getting the diatoms

And I'm using red Sea nitrate test kit

 

[Pntbll687]

But I agree that the matrix is not the root of the problem

I actually agree. I think it was a combo of getting the detritus it was holding out and vacuuming the sand bed that brought nitrate down substantially.

It just got me thinking. Am I taking advantage of the biomedia I have? Or is it just sitting there?

I think I might try something like "Donovan's nitrate destroyer" or carbon dosing such as using bio pellets. I can easily plumb it off my manifold and not have to add any plugs to the tank

 

[45ZoaGarden]

I would go the natural route and grow cheato in your fuge section.