DIY Automated dosing/topoff

[scolley]

D*mn Andrew! I wish you had seen this earlier too!

I've booked marked that - great stuff! I'm sure will need it soon. Thanks for the post!

[bharada]

Originally Posted by Wasserpest

These are the Raindrip drippers from HD, one side black, one side red, and they come in 1/2 gal/h and 1 gal/hour flavors. But they are made for 20+ psi so I doubt a powerhead would get them dripping at all.

I was at OSH today and I saw the ones you're talking about. So with the low pressure of the powerheads the 5gph (or even 12gph) emitters may be a better bet.

[bharada]

Originally Posted by TechoJunkie

Yeah I have a pump that delivers 0.16ml/min so a 6-8 minute cycle each day should deliver what I require. My concern is if I'm injecting what is such a small volume that by the time it fills a non-return valve it might be sitting there for a while before it enters the water column.

My only concern here would be the ferts crystalizing and clogging up the tube...especially if you're using really small ID delivery tubing. I have my PPS solution mixed in a water bottle and use the cap for measuring the doses. After a couple of days the residue from the cap threads forms a decent crust on the bottle.

Since I can't see backflow being a problem with the pumps so I plan to keep my drip tube submerged to prevent this from happening.

[scolley]

Originally Posted by bharada

After a couple of days the residue from the cap threads forms a decent crust on the bottle.

Wouldn't that be due to evaporation? And if so, if there is no air in the tubing, I would assume there is nothing to fear, regardless of diameter. No?

[SCMurphy]

I'd be easier to reduce the concentration of the solution that you use in the automatic feeder. You'd have to increase the amount of solution you dose, but that should be easy to do.

[bharada]

Originally Posted by scolley

Wouldn't that be due to evaporation? And if so, if there is no air in the tubing, I would assume there is nothing to fear, regardless of diameter. No?

I'm more concerned that the solution would start evaporating from the tip in...forming a plug at the end of the line.

[scolley]

Originally Posted by bharada

I'm more concerned that the solution would start evaporating from the tip in...forming a plug at the end of the line.

Ah - now I understand... This is an issue if, and only if, you have this set up as an open drip. Not an issue for inline injection. Please correct me if I'm wrong.

[bharada]

Originally Posted by scolley

Ah - now I understand... This is an issue if, and only if, you have this set up as an open drip. Not an issue for inline injection. Please correct me if I'm wrong.

You are correct, sir! Since I don't plan on injecting inline I'll just keep the drip tube submerged..

[TechoJunkie]

Ok. So I think I'll submerge the tube and be done with it. At 1/16" ID it won't backflow and empty the tank in a hurry (not at all with the pump connected).

[Betowess]

Anyone see any reason why one couldn't put a T on an SP100 or SP200 peristaltic pump and run from one resevoir of trace ferts to two tanks of similar size (a 90 gallon with a lot of substrate and wood and a 65 gallon with less substrate and very little wood). Perhaps I could slow the feed rate by changing the amount of hose to one of the tanks?? Or is this $65 dollars savings asking for serious trouble?

[filipnoy85]

Whoa... talk about bring a thread back to life!

I figure if you could afford an autodosing perstaltic pump, you could probably go the extra $65 and avoid the risk....

As for trouble, are you worried about over dosing the 65 or under dosing the 90? I guess under dosing would be better than over dosing if you fertilize from the same line.

[dipan]

Originally Posted by Betowess

Anyone see any reason why one couldn't put a T on an SP100 or SP200 peristaltic pump and run from one resevoir of trace ferts to two tanks of similar size (a 90 gallon with a lot of substrate and wood and a 65 gallon with less substrate and very little wood). Perhaps I could slow the feed rate by changing the amount of hose to one of the tanks?? Or is this $65 dollars savings asking for serious trouble?

You could use one of these for less than a buck to increase resistance on the smaller tank line. A longer line would also increase resistance and decrease flow. This would be adjustable, though ... Might take some playing with to get it just right ...

linky

Or, a more expensive option, but more accurate:

linky 2

[Betowess]

Yeah. dipan. Great links! I've been trying to remember the Aquatic Eco systems name for a while. I just bookmarked it. I could definately use either of those for my two different AS 606 pumps dosing the macros. I ended up putting some lead weight in a brass tee on one to slow down the flow to get the right amount of dose out after tediously adjusting hose length etc.

Still trying to decide if I might try just one or two of the SP100 peristaltics. These links make getting just one of the peristaltics a definate possibility.Thanks again.

Also, thanks Flipnoy.

[donaldbyrd]

Just curious for those of you that are auto dosing into the tank do you have the line in the water or above it and dripping into the tank? Also how do you have the tubing attached to keep it in place?

[Wasserpest]

Wow, thanks for bringing up this post... back when it was new, it inspired me to do the powerhead dosing which is still working great for macros.

Anyways... If you run it for one or a few minutes each day, you would probably want to submerge the line, to prevent the slowly dripping fertilizer from drying up and clogging the outflow.

That leads to two issues... 1) water creeps back into the dosing line and 2) there is a possibility of a siphon and water on your carpet. I guess when using peristaltic pumps neither are an issue. Using a tiny hole as the outlet would remedy both issues as well.