Fertilizer and Gravel thickness

**Nateynoo** · 31st Aug 2009, 10:12

Hi guys

I am in the midst of constructing my first planted tank. my tank is a two feet one and i just put a layer of fertilizer at the bottom before plonking in the gravel on top.

I need some advice regarding how much gravel i should put in the tank cos from the outside it looks pretty thick (1.5 inches) and im just wondering if my plants are eventually able to tap onto the fertilizer?

all advice will be appreciated!!

**magpie** · 31st Aug 2009, 11:57

Hi,

Why don't you get those soil that has fertiliser on it. Eg. like Magic Soil and GEX soil. That save the trouble of adding fertiliser at base and topped up with gravel.

**Nateynoo** · 1st Sep 2009, 09:49

Hi Magpie

well the shop assistant told me otherwise. he said to buy a pack of fertilizer and a pack on gravel.

his first instructions were to dump all the gravel over, but i've only used half and it's 1.5 inches high

**goody992828** · 1st Sep 2009, 13:00

Hi

I guess the question is what plant do you intend to put in your tank, eg if you want plant that have long stem and need to be rooted for stability. Than I guess 1.5" height might not be sufficient. My thought should be 3" at least

This is just some of my thoughts

**green palette** · 1st Sep 2009, 13:07

yup i agree with goody..generally speaking for a planted tank, the thickness increase from foreground to background. As for foreground, i guess 1.5 in or about 3 cm will be suffice for your smaller plants however, the background plants will require more rooting and hence about 8cm thick or gravel for the back is recommended. Unless of course if you intend on growing rhizomes (plants on wood) then you'll need not have such a thick layer of gravel..yup thats generally speaking =) hope that helps..

**David Moses Heng** · 1st Sep 2009, 16:32

Originally Posted by Nateynoo

Hi Magpie

well the shop assistant told me otherwise. he said to buy a pack of fertilizer and a pack on gravel.

his first instructions were to dump all the gravel over, but i've only used half and it's 1.5 inches high

er... may i ask where is this LFS? Like the rest of the brothers who have pointed out, it is actually easier for you to use nutrient pack substrate like GEX, Nisso Custom soil, ADA and many others. But then again, each individual has their own preference. Like for myself, after trying out GEX, i have switched to just using garden soil with lapis.

For thickness, i usually do 4 inch behind to 2 inch in front.

Just my 2 cents worth of sharing.

**pustefix8965** · 4th Sep 2009, 16:16

The purpose of the gravel is to prevent the base fert from clouding the water. The recommendation is 1-1.5 inch of gravel. If you want to increase the thickness, you should increase the amount of base fert.

FC · 13th Sep 2009, 15:11

Potent Fertilsers
Thickness of fertiliser and gravel only matters when you are using more potent bottom fertilser like Dennerle, JBL, root tabs, etc. Such fertilisers need topup of inert gravels or soils to avoid excessive nutrient leakages which can cause algae or harm the fishes. The topup is about 1 to 3 inches depending on the fertilser thickness and tank size.
Such setup is best suit (not limited to though) for:
- larger and hungrier plants
- high tech CO2 injected and temperature controlled tank

Soil
Good processed soil like ADA soils are ultra-low in fertliser content and needs no inert gravels topup. These soils greatest pros is their softness (soft edges) and slightly acidic content that greatly encourage root (fine roots especially) growth. In long term, the soils works via waste to nutrient recycle. However, water change and/or nutrient supplements like traces are essential here.
Such setup is best suit (not limited to though) for:
- foreground amd midground plants
- slower growers

**bitstream** · 19th Sep 2009, 22:57

ive used 1.5 inch of gravel on top ADA substrate. I've found that my hairgrass doesnt spread very well as the roots are not really able to penetrate the gravel. If you intend to fully carpet the bottom of your tank with hair grass or the likes, i dun suggest putting gravel. Yes replanting will foul the tank water, but i find it settles very quickly

FC · 22nd Sep 2009, 23:34

Originally Posted by bitstream

If you intend to fully carpet the bottom of your tank with hair grass or the likes, i dun suggest putting gravel. Yes replanting will foul the tank water, but i find it settles very quickly

Right! I experienced the same.

**bitstream** · 22nd Sep 2009, 23:40

Ok after reading your post again, I realise you have already dumped the gravel onto the substrate. If u intend to carpet the bottom with plants, I suggest u suck up the gravel and get rid of it before you tank becomes mature. After 8 months, I decided to remove the gravel layer and replant, I can tell you, its no joke. Best to do it now before everything fully settles in, or else good luck