Tank volume OR amount of water it holds

[tim85]

Hi everyone,
Just bought my 2' tank. The volume stated is 60L. I also have 2x55W PLL lighting unit for that tank and 1 bag of ADA Amazonia II .

I have pressurized CO2 and all the dry fertz (KNO3, KH2PO4, MgSO4, CaSO4) and CSM+B.

1. Now before I start calculating the number of tsp required to dose my tank, what amount of water do I use as the basis of my calculation. Do I base it on 60L or do I base it on 60L less the volume of ADA soil (9L in this case) ?

2. My tap water is soft, any recommendation on the amount of fertz that I should start with?

TIA.

--
Tim

 

[JDowns]

If your dosing EI, either volume would yield the same dosage. If your dosing PMDD then IMO either would be fine. The difference in dosage shouldn't cause you any problems. Personally I dose off the volume of the tank, since I'm reserved to excess nutrients that we dose don't cause algae. Dosing off of the tank volume isn't going to put you into any extremes either way.

 

[Mr Fishies]

I read this forum a lot, I find never post since someone seems to have already asked my questions...and answers come too fast! In this case, I almost found my answer but not quite.

I have this same question, but my tank is a Perfecto 75G. By the time I look at the effective volume of the tank (less glass thickness, rim allowance etc), I am looking at about 66G (65.9). Subtract 6 bags of Eco (easily 5G), a few chunks of wood and I am down to something more like 60G unless I've gone way off in my math. It seems I've got a volume "discrepancy" equal to the original posters tank size.

I know they are only guidelines to start from and we really need to observe and tailor it to the amount of plant, light, CO2 etc. Looking at the "EI light" suggested dosing chart, according to the label on my tank vs. real volume, I'd be dosing 10.5 ppm more NO3 and 6.6 ppm of K if I went to the label volume of my tank vs. the effective volume. Which should I be using?

Since I called my tank a 60G for dosing purposes, I'm wondering if I am too lean in my doses and I should be using the next higher bracket for my routine.

 

[meatus]

With EI you can base it off of the original 75G volume. The weekly water change is removing any of the excess ferts anyway. I also have a 75G and I dose the amount for 75G and have no problems. I don't know however if you're shorting your tank anything by going off the 60G amount though. You may still have enough ferts for the plants with that but I'm not sure. Just go off the 75G amount and make sure you get your water changes in.

 

[Biollante]

What meatus said.

Unless you are using your tank as a pauldarium, filling it a third or two-thirds, just start with the tank volume.

EI stands for Estimative Index, we estimate, as long as you are doing water 50% changes at least once a week, you are golden.

Simply adjust dosing, up or down from the maximum volume.

I always believe people are doing themselves a favor by dosing ‘heavy’ and sticking to moderate light.

I also recommend planting heavy, in particular when starting out or when you have a problem or when you can see a space.

I have been labeled a ‘nutrient type,’ I gather that is a bad thing here, so let me state for the record; this all assumes good general practices, reasonable filtration and circulation (more the better, in this plant’s opinion). Lest anybody be mistaken, I also believe in good strong CO2, I look at 30 ppm CO2, a minimum and prefer around 40 ppm, though I have recently discovered my much-vaunted 40 ppm was actually more like 33 ppm, oh well, live and learn.

Biollante

 

[Tom Barr]

I read this forum a lot, I find never post since someone seems to have already asked my questions...and answers come too fast! In this case, I almost found my answer but not quite.

I have this same question, but my tank is a Perfecto 75G. By the time I look at the effective volume of the tank (less glass thickness, rim allowance etc), I am looking at about 66G (65.9). Subtract 6 bags of Eco (easily 5G), a few chunks of wood and I am down to something more like 60G unless I've gone way off in my math. It seems I've got a volume "discrepancy" equal to the original posters tank size.

I know they are only guidelines to start from and we really need to observe and tailor it to the amount of plant, light, CO2 etc. Looking at the "EI light" suggested dosing chart, according to the label on my tank vs. real volume, I'd be dosing 10.5 ppm more NO3 and 6.6 ppm of K if I went to the label volume of my tank vs. the effective volume. Which should I be using?

Since I called my tank a 60G for dosing purposes, I'm wondering if I am too lean in my doses and I should be using the next higher bracket for my routine.

Well, another option, not taking anything away from what else has been said earlier............

If you have less than say 3w/gal of PC/HQI/T5 lighting, then you can add less without issue, say for a 60 Gal instead.

Should not hurt anything.

Light is a factor there, but if you are 2-2.5w/PC/T5 etc, then you should be fine.
the rest is CO2 or CO2 related

Regards,
Tom Barr

 

[Mr Fishies]

With the intent of low maintenance and not having to trim weekly, my 75 is pretty low light with a single 96W CF over it and I don't run much CO2 either, maybe 15 ppm, so that's what motivated me to keep doses low, but I assume because it is heavily planted, I seem to quickly see the effects of a missed dose here and there.

Thanks for the replies and the reminder (which I needed) that my water changes will take care of the nutrient "leftovers". I think based on what was said, I'll up my doses a bit and see what happens.

 

[Tom Barr]

With the intent of low maintenance and not having to trim weekly, my 75 is pretty low light with a single 96W CF over it and I don't run much CO2 either, maybe 15 ppm, so that's what motivated me to keep doses low, but I assume because it is heavily planted, I seem to quickly see the effects of a missed dose here and there.

Thanks for the replies and the reminder (which I needed) that my water changes will take care of the nutrient "leftovers". I think based on what was said, I'll up my doses a bit and see what happens.

When you do, realize there may be issues since you need to scale everything up along with nutrients, CO2 is critical.

If there was some nutrients limiting, then the CO2 demand is downregulated.
If you add non limiting ferts, CO2 is upregulate. With lower light, you might be okay.

I'm not sure why many have issues with CO2, 15ppm is painfully low IME.
I have bred discus and angels, cories, maybe a dozen other species at 30-45ppm of CO2 and I calibrated the CO2 measurement method and probe.

So I KNOW the ranges.

Most of the nicer high light tanks have about that range. Most claim less etc, since they do not measure the CO2 carefully..............

Regards,
Tom Barr