# tpn+ help with dosing



## miggsy (17 Sep 2008)

Hi All

Can someone help me out regarding dosing my tank with tpn+

tank dimensions are as follows

36x12x18 been up and running for a week  just want to know if best to dose daily or weekly and how much 

Many thanks


----------



## LondonDragon (17 Sep 2008)

Tank that size I would start with at least 5ml per day, if you have a good plant mass and also good light and CO2.
If you post the full setup and a photo would help


----------



## miggsy (18 Sep 2008)

many thanks

full set up includes arcadia 4x39w overlamp two lamps on 12 hours then other two for a two hour midday burst

full c02 pressurised system fluval 404 external with 300w hydor external heater seachem substrate with a 2cm silver sand top layer will try and get a pic up


----------



## LondonDragon (18 Sep 2008)

Nice setup, ever thought about going the EI method? Would save you a fortune, but 5ml might be on the low side, you might have to up that futher soon enough, what you dosing at the moment?


----------



## miggsy (19 Sep 2008)

have thought about the ei method but im still trying to get my head round it really


----------



## JamesM (19 Sep 2008)

miggsy said:
			
		

> have thought about the ei method but im still trying to get my head round it really


What's to get your head around? If there is something that confuses you, ask and we'll help you out  It really is simple


----------



## Egmel (22 Sep 2008)

miggsy said:
			
		

> have thought about the ei method but im still trying to get my head round it really


They're right there's nothing to get your head around, but I can never remember what I'm meant to be dosing on what day of the week!

James has kindly calculated a recipe for TPN+ so you can make it yourself to keep costs down.  I would say it's even easier than baking a cake! http://www.theplantedtank.co.uk/allinone.htm

You can get all the basic ferts from Aqua Essentials or Gardens Direct (though the trace is higher in copper from the latter) and the Potassium Sorbate and Ascorbic acid are easily found on Ebay.  To make measuring easier James kindly pointed out that 0.4g E300 Ascorbic Acid = 1/8 tsp and 0.2g E202 Potassium Sorbate = 1/16 tsp (most measuring spoon sets have a 1/8th tsp measure on them.)

Hope this helps on the costs front 

As for how much to dose, that depends on your plant mass and you inhabitants.  If you have sensitive inhabitants then you should keep the dose low enough that you don't upset them but high enough to feed all your plants.  I'm using the trial and error method, I started with the recommended dose from tropica and have been gradually increasing it.  My shrimp have recently become more lethargic so I'm going to try dropping back a couple of levels and see how it goes.

I'm sure there's a more scientific way of working out the required dose, but this seems to be working for me


----------



## altaaffe (22 Sep 2008)

I was always wary of dosing using EI & dry ferts but took the plunge a couple of months ago, there is plenty of great info on this site for it.  Although I have found several different recipes along the way, I now use Tom Barr's (as provided by aqua essentials) and have had no problems.  I have the mixes set up for the specific tank in old Tropica bottles with which day of the week it gets dosed & how much written in marker on the bottle.  I also keep the old 2l bottles from my Aqua+ conditioner and make up a 2l dose of NPK at a time, as I empty a bottle for a tank I just refill from the 'store' bottle.  On the back of the large bottle I write how many grams of dry powders go in to make up each 2l.  This way if I ever forget a detail it's right there.


----------



## aaronnorth (22 Sep 2008)

> I'm sure there's a more scientific way of working out the required dose, but this seems to be working for me



start with 1ml per 20l. This is what i was told when i 1st started. then adjust it from there.


----------

