how does hardness affect my plants?

bluemeate

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Sep 9, 2008
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so im wondering how hardness and dissolved minerals and what not affect plants, ive heard one thing about there being way too many dissolved solids in the water so that limits the amount of nutrients that can get around or something. Ive also heard something about how at a higher ph the CO2 becomes CO3 and most plants have trouble breathing that

the plants i have arent growing all that fast or full yet i hear theyre all really easy to grow plants. i cant name all of them but i do have amazon sword, red and green wedntii, mini sword or something, something else, anarchris, and naja grass...

or is the slow growth probably due to my substrate or nitrates or something else?



heres my parameters
55gal
pea gravel substrate, i put like 3 root tabs in about 6 mo ago
rena xp3 filter
temp is 80
petco measured my alkalinity to be 300mg/L (could possibly be much higher than that since thats as much as they test for
and they also tested my hardness to be 300mg/L also
my ph in my tank is 8

nitrates are stuck at 0ppm (but the next incriment on color chart is 5ppm so i dont know what that really means)
my bioload is about 25 1-2in fish,
my lighting is 2 t5ho bulbs (one is marine, the other is idk) for about 8hr a day
 
so im wondering how hardness and dissolved minerals and what not affect plants, ive heard one thing about there being way too many dissolved solids in the water so that limits the amount of nutrients that can get around or something. Ive also heard something about how at a higher ph the CO2 becomes CO3 and most plants have trouble breathing that
There are two hardnesses, carbonate (KH) and General (GH). It looks like you have ~16-18 GH . That's high. I have seen parameters for most planted tanks of <10 GH, and KH 4-8.

the plants i have arent growing all that fast or full yet i hear theyre all really easy to grow plants. i cant name all of them but i do have amazon sword, red and green wedntii, mini sword or something, something else, anarchris, and naja grass...

or is the slow growth probably due to my substrate or nitrates or something else?

heres my parameters
55gal
pea gravel substrate, i put like 3 root tabs in about 6 mo ago
rena xp3 filter
temp is 80
petco measured my alkalinity to be 300mg/L (could possibly be much higher than that since thats as much as they test for
and they also tested my hardness to be 300mg/L also
my ph in my tank is 8
nitrates are stuck at 0ppm (but the next incriment on color chart is 5ppm so i dont know what that really means)
my bioload is about 25 1-2in fish,
my lighting is 2 t5ho bulbs (one is marine, the other is idk) for about 8hr a day
I am going with they aren't growing because there is no NO3 (possibly also VERY low CO2 at pH 8). Also, the root tabs are WAY gone, and swords are HUGE root feeders. You need to be dosing much more fertilizer and doing something about the CO2.
 
I think you have the wrong lights. A marine bulb?? Is that actinic??? Your K rating must be in the 6500 to 10000K to be of any use to your plants. Outside of that is just for show, the plants cannot use it.
 
I think you have the wrong lights. A marine bulb?? Is that actinic??? Your K rating must be in the 6500 to 10000K to be of any use to your plants. Outside of that is just for show, the plants cannot use it.

I disagree and still have not seen data to convince me otherwise, but a 50/50 or actinic bulb is NOT a waste, if the other bulb is a 6700K or something similar. Tropical FW plants get that light all the time, while it may not be super-amenable to photosynthesis, I think my plants do better with my 50/50 bulbs on (in conjunction with my 6700K bulbs), than without. However, if his other bulb is another 10000K, I agree, he needs to get daylight bulbs in there.
 
well its a "glo" brand fixture that only works if both the bulbs are plugged in. one bulb is "marine-glo" and the other which im hoping is good for my plants is the "life-glo" bulb which tbh, i know nothing about.

*edit, just looked it up*
6,700 degreeK T-5 HO fluorescent bulb
yeah the marine one is one of those bluish bulbs, i tried to unplug it to discourage algae but w/e ill just get out the habbit of leaving my lights on for like 30 hours at a time lol


I am going with they aren't growing because there is no NO3
also i only gravel vac 1/3 the tank like every other month and theres sooo much crap in there, so i dont understand how the nitrates can be stuck at 0ppm
 
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I think the Marine-Glo is an actinic bubl, and the other is maybe a 6700K. But not sure, have never used that brand.
 
well its a "glo" brand fixture that only works if both the bulbs are plugged in. one bulb is "marine-glo" and the other which im hoping is good for my plants is the "life-glo" bulb which tbh, i know nothing about.
I think you have identified your problem. http://www.hagen.com/uk/aquatic/glo/GLOT5_LightProg7_EN.cfm According the manufacturer's website, Life-glo is designed for planted aquaria.

also i only gravel vac 1/3 the tank like every other month and theres sooo much crap in there, so i dont understand how the nitrates can be stuck at 0ppm
I don't think vaccuuming the gravel has any effect on your nitrates. You didn't mention if you are feeding the plants. With a zero nitrate reading, I assume not. All the nitrates from fish pee/poop is being consumed by plants, but that is obviously limiting your plant growth. Dose some nitrate based fertilizer, get your NO3 to at least 10ppm consistently, watch your plants take off, followed by the algae. Then you will have to start doing CO2 of some sort.
 
2 things regarding the low Nitrates

Make sure you are shaking it very very very well, and for more than the alloted 30 sec.
Test. if you still get nothing then..

2. Buy some Seachem Nitrogen. Capful>wait 24 hours>test..countinue until you get readings.
 
All the nitrates from fish pee/poop is being consumed by plants, but that is obviously limiting your plant growth. Dose some nitrate based fertilizer, get your NO3 to at least 10ppm consistently, watch your plants take off, followed by the algae. Then you will have to start doing CO2 of some sort.
how about just getting more fish?
 
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