brad

http://www.thekrib.com/Plants/Fertilizer/roots.html

I imagine that most of this has challenged as it`s nearly 10 years old.

Is it possible that plants grow better when we dose the water colomn because it`s much easier to do and do consistently? t`s hard to keep adding nutrients to the soil. Easy to make sure they`re in the water colomn.

Obviously, long term, water colomn fertilization is a much more sustainable method, but short term, assuming all the nutrients are provided through the substrate, do the plants still do better with plain gravel and fert in the water?

Phil Edwards

No, the special aquatic plant substrates aren't necessary. They just happen to have qualities that benefit plants more than smooth epoxied gravels. River sand, pool filter sand, and poultry grit of the proper sizes are just as good and maybe even better. Personally, I'm partial to collecting sand and gravel from my local creeks. Unless the creek is really muddy the mixture of grain sizes is generally perfect for growing plants.

Regards,
Phil

urville

so just to ease my curiosity then you could put the same root tabs in a container inline say... this is if your using canister filtering or hob... in that filer as the last thing before it goes back to the tank and you'd still be dosing the column right?

MatPat

I would not put root tabs into the water column directly. Some, if not most, root tabs contain ammonia or ammonium, which could lead to algae problems. These type fertilizers are best if used in the substrate.

If you want to dose the water column get some KNO3 and KH2PO4 or use Flourish Nitrogen/Phosphorous. Plain old Stump Remover (KNO3) or Fleet Enema (PO4) can be used for the water colun and are pretty cheap ~$5 for both, and will last a long time.

urville

oh okay that makes sense... you wouldnt happen to have a link or any insight as to dosing a non-co2 tank with these products would you? I use Flourish Excel instead.

MatPat

Here is a link for the Estimative Index for non-CO2 tanks:
http://www.barrreport.com/forums/showthread.php?t=395

Near the end of the article, Tom recommends adding 1/8 tsp KNO3 (~6ppm) and 1/32tsp of KH2PO4 (~1ppm) to a 20g tank weekly or every other week.

Here is a link to help you convert Flourish products (should you decide to use those) to PPM:
http://www.fishfriend.com/fertfriend.html

Stump remover is KNO3. Some folks recommend the brand Greenlight, but I used Spectracide for over a year with good results. I can give you more help with the Fleets dosage if you need it.