Constant Zero Nitrate

[Ben C.]

Hello!

I've got a couple nano 5.5 gallons (yay apartment life) that are stocked with 6 rasboras each, with the usual smattering of snails and shrimp. I feed pretty generously, and am dosing 4 pumps of easy green a week (2 pumps twice a week) and I'm still sitting at zero nitrate! I pull fistfuls of dwarf water lettuce and duckweed every week too. One doesn't have any algae at all, but one is grows a manageable amount each week. My question is, do I stock heavier? Or just keep pumping more fertilizers? I hesitate because 5.5 gallons isn't much, and I don't want to upset the balance too much. But man, it's a lot of fertilizers for such a tiny tank. Thanks!

[Guest]

I think you could definitely add more rasboras. I know they'd appreciate it. I don't know what type you have specifically, but think that you could do like 12-15 chilli rasboras (or similar in size) and about 10 of a larger species like the lamb chop rasboras. If you're worried about overloading your tanks, add fish slowwwly. 

[Ben C.]

That's what I've been thinking too! I have Emerald rasboras and Blue Neons - only hesitation is that I've only found the Blue Neons from Aqua Huna and they're so fragile, usually half are DOA 😞 ends up an expensive venture with shipping costs..

[CT_]

You could consider keeping less floaters.  Ie pull more or every week.  In my 15g I restrict the floaters to one corner.  They'll pull nitrates out at a rate proportional to their numbers.

[Isaac M]

Hi @benchilton, 2 pumps of Easy Green provides about 12 ppm of nitrates to a 5 gallon. So you are adding about 24 ppm of nitrates a week. If the plants are growing so quickly that they remove it all, then you have a great balance going on.

What do you use to test your nitrates by the way? If you use the api test kit, the nitrate test requires that the 2nd bottle be shaken for 30 seconds minimum before you add the drops to the test tube. If this step is skipped, a false zero reading will be given. Just something I wanted to mention just in case. 

[Ben C.]

@CT_ only reason I hesitate about the floaters is because it provides so much cover for the fish. I suppose I could test and see if it affects their behavior, the floaters will be back soon enough haha

[Ben C.]

@Isaac M I was using API test, and shaking the devil out of it, the main reason I hate using it haha. So I tested again today with the new co-op strips today and got the same result. I agree it's a good balance, just wish I didn't have to supplement so much.

[Isaac M]

@benchilton haha that is exactly why I have retired my api test kit as well for the co-op test strips haha that, and the time it takes and the colors. I do not like the colors of the api kits, it is hard to read sometime depending on the light. 

But yeah, you just have a good balance going.  I would say add more fish if you do not want to keep adding fertilizers. I mean, you probably do not even need to add the fertilizers you add now but it will slow down the growth of the floating plants.

 

[Ben C.]

@Isaac M yeah I wasn't testing nitrate for a long time after getting them established because it's just such a pain..the strips are great. Thanks for the advice, I think I will add more if I can find some healthy ones at the LFS to fill out the herd.

[SWilson]

just curious what your substrate is.  We've noticed in our tanks that use CaribSea Eco-complete, the Nitrate is also constantly zero or very low, regardless of stocking/feeding/fertilizing.  Tanks that don't have that substrate have a more normal accumulation of nitrate each week.  

[Ben C.]

@SWilson Curiously enough, it does have some Eco-complete, that I had used from an older aquarium to seed it, although it also has inert sand. Time to set up a new aquarium with only eco-complete, for science right??

[SWilson]

@benchilton - totally for The Science!!  😁

(has absolutley nothing to do with the Petco sale rn) 

[Ben C.]

@SWilson what there's the petco sale?? You shouldn't have!!

[anewbie]

This is my 5 gallon tank. It has measured sub 5 nitrate - probably around 1 or 2 for the past 6 months. Stocking is 6 neon 4 ember 15 mystery snails and some number of shrimps (shrimps aren't doing well in this tank). There are two speculations for low nitratre: anaerobic activity in the substrate and root floaters which grow massive in this tank (my water lettuce are blooming!):

 

[SWilson]

@anewbie that is a very cool tank!  Is the psychedelic color look from your lights?  If so, what lights are you using? 

@benchilton oohhh yes, at least where I am (Bay Area, CA) Petco is having the sale...what I was told is that it is no longer $1 per gallon, but a number of tanks (I think, 10s, 20s, 40b, 55, and 75) are 50% off.  I dunno if that change is permanent or just right now.  For some of the sizes it does end up being equivalent to $1 per gal, or close.  Happy shopping!! 😛 

[anewbie]

15 minutes ago, SWilson said:

@anewbie that is a very cool tank!  Is the psychedelic color look from your lights?  If so, what lights are you using? 

@benchilton oohhh yes, at least where I am (Bay Area, CA) Petco is having the sale...what I was told is that it is no longer $1 per gallon, but a number of tanks (I think, 10s, 20s, 40b, 55, and 75) are 50% off.  I dunno if that change is permanent or just right now.  For some of the sizes it does end up being equivalent to $1 per gal, or close.  Happy shopping!! 😛 

It was a 12 inch black box from nilgoc. This is a super bright light around 400 par at the bottom of the tank. It was a test. I've now changed the light (about a week ago) to a 12 inch wrgb2 and should probably take an updated picture. The reason you are seeing the 'psychedelic' colours is due the coarsness of the led in the black box and proxmity to the tank (sitting on top). I've been running tests with different equipment to decide what i want to use a for a 400 gallon tank i will setup next year. 

[Ben C.]

@anewbie beautiful tank! I love the overgrown look. And I agree, the floaters take up so much of the nitrate! I constantly have to remove more haha

[Ben C.]

@SWilson just saw the sale. Definitely gonna pick up a 55 as it looks like the 75's are all gone!!