Going to hi tec


Prolific Poster
Jan 21, 2007
I have just set up my 180g low tec planted tank. I am very happy with it at the moment esp. the low maintenance.
I may decide to convert the tank to hi tec ie. adding CO2 ferts and more lights in the future, especially if i can't get that luxuriant planted growth.
My concern with this transformation if i do proceed is water changes. That is why i don't like Tom Barr's EI.
I have had this tank as a fish only tank for 10 years now housing big american guapotes. I have been doing 70-80% water changes weekly over all those years. Hence you can see why i have a repulsion in doing any more water changes, esp. on a tank my size.
This leads to my question. Can i have a hi tec tank with no water changes? Can i dose the ferts and test the water on a weekly basis for Ca Mg NO3 K and P04 and add these as required? I know it means i need to use test kits that that does not concern me. At least it won't take 2 hours.

Tom Barr

Staff member
Jan 23, 2005
Well, it can, but not with a bunch of large dirty Cichlids, that's asking for trouble.
You can do it, it is possible, but it's much harder and you are placing barriers around your method here that are not required.

Do not paint yourself into a corner.

I would highly suggest taking another approach here.
Hard plumb the tank.

Add a simple large diameter drain bulkhead that drains outside to the lawn etc or the drain in the house etc. Add a mix of hot/cold water for the refill.

Each fill and drain pipe has a valve to turn off/on.
This will save you tons of labor and make re setting things much easier.
It's a hassle to do this, but the long term effect is awesome.

You may also use 1/4 or 3/8" hard poly tubing for drain and fill as you can hide this easier etc, snake through the walls etc.

You can hire a plumber if you really want to also.
The cost will be worth it.

You can spend the cost of that easily on a test kit set up and then if you paid yourself say 5 $ hr, how much time would be wasted?

Do you like getting wet to clean and prune the tank? Draining the 24" to 12" deep tank makes working on it much easier there!

What about plant and fish health?
Do you think general upkeep and maintenance via a weekly water change will provide better or worse environments for them?

As you increase the rate of growth and go hi tech, you also create less room for errors, you have to respond faster and cannot put things off nearly as much.

You will need to calibrate the test kits to make sure that their readings are correct as well.

Basically you will need to learn an entire new skill set, or you can do water changes. There are trade offs for both approaches.
Given that you like larger cichlids, the wiser choice would be large frequent water changes, just like Discus advice.

That being said, with moderate loading of fish, you can get away without water changes, but it can walk a razor's edge, and that method like water changes, is self imposed.

You have some choices, but the trade offs and your personal habits play a huge role also. Folks generally slack off a great deal with test kits over time.

Even the best Marine tanks and astute detailed folks there have issues with their batteries of Lamotte test kits.
Marine water changes cost more and many of them have massive tanks, so the trade offs often are worth while there.

Automated water changes using a float switch and a solenoid can be very effective, Alan has a massive 185 gallon packed with huge fish, he does 2x a week 30% weekly water changes on timers.
The tank drains a fills 2x a week for 2-3 hours using 1/4" and 3/8" lines.
He never does a water change manually.

I'd prefer to outwit test kits/labor/guess work and labor of doing manual water changes, that's why we have brains:cool:

I would rather use the effort to avoid more future work, both test kits and water changes.

So what I suggest avoids both.
This gives you the best and simplest method for the long term. You have had this tank for over 10 years, so set it up to avoid work, or at least the type of work that you do not like. I like gardening personally, but hate test kits and water changes as much as the next guy, maybe more:cool:
But I do methods and make systems to get around all that mess.

Some folks will say they cannot do an automated system for what ever reason.
But if they can afford all this, can do all the test kits etc, they can also figure out a way to automate and remove the labor in doing water changes either entirely or at least a large amount if they put their heads into it.

Tom Barr


Guru Class Expert
Jan 12, 2007
Dorset, UK
This is probably a really silly question I know, but Im going to ask it anyway as one day, when I have a large tank Id like to automate the water change.

How do you get the holes in the tank for the bulkhead fittings? The rest I can get my head around fairly easily being very practical, but that bit illudes me.


Prolific Poster
Jan 2, 2007
And I'm going to ad to Frolicsome's question: How do you deal with dechhlorinating the water when you plumb a fill line right to you tank?


Lifetime Charter Member
Lifetime Member
Jan 24, 2005
Sacramento, CA
You get holes in a glass tank by drilling or cutting them with diamond coated bits. This is obviously not for the faint hearted, but many people do it sucessfully. You do have to learn the technique first.

I use a continuous water change system, with a small trickle of water constantly coming in and an overflow taking care of keeping the water level constant. I run the water though an activated carbon filter, made for "whole house filtration" of drinking water, to eliminate much of the chlorine. I have no idea if it is working or not, but I haven't had any problems that I can blame on chlorine. My system replaces about half of the tank water a week. If you use a plumbed in water change system that only works when you turn it on, you can just add the dechlorinator as the replacement water fill starts. That's how I do regular water changes.

Tom Barr

Staff member
Jan 23, 2005
See how lazy Vaughn really is? :p

It takes years to learn how to be that lazy:eek:
You can jump right to that stage asap.

I typically have the tank pre drilled when I buy them.
I have generally 3-4 holes in any tank on the bottom.
2 are for the overflow drain and return.
I use the ball lok pipe for my return.

The other 1-2 drains I use a rainbow plastics screen and these bulkheads are placed away from the over flow. These are the actual drains for the tank. 2 is ideal for larger tanks. The screen prevents fish from being drained.

One of the drains is about 8-12" up, the other is very low, 1-2 " up from the bottom, or uses a stand pipe to keep it right at the gravel level to keep gravel from being sucked in when draining.

For big drain jobs, the lower one is used, for smaller jobs and normal routines, fish loads, they need more water, so the upper one is used.

These drains are connected to a cansister filter, these are sealed filters, if you want mechanical filtration, Ocean clears are good etc or smaller Ehiems/Via Aqua and Magnums etc.

On the drain intake side of the these filters, you add a Tee and a valve. The valve is your drain and the closed valve sends the water to the filter otherwise.

You can add a solenoid (say a 1/4") to this junction (I'd still install a valve for manual work etc!) and place it on a timer to drain the tank through this small line for say 2 hours 2-3x a week.

The refill can use a small vertical electronic float switch like spectrapure makes which can sit inside the tank or sump.

As the water drains slowly, the float valve turns on and refills the tank automatically.

Note: use small slow flows for this, if the drain is too fast, the tank will empty!
If the refill cannot make up or you run the sump dry etc, that can cause issues also.

Main thing is to do the automated stuff slowly when it comes to flow/drain rates.

With semi automated, manual valve turning for fill/drains is the best option, then you should go huge/large pipe diameters.
So that's the trade off there.

Safety is huge, so do not get any crazy ideas to drain the tank fast and refilll on an automated system.

You can be there for those events, but the slow exchange can be done easily on a timed system.

And with the timers, you can do this 2-3-5x a week, 1-2-3-4 hours etc, whatever you want.

So if you use EI, the levels are much lower in the build up and that allows you even better control without much difference in work/labor.

The long term results are: very good fish health and plant health, high optical clarity, clean tanks, no disease, ability to keep huge fish loads*(why do discus folks do large frequent water changes when they feed like crazy?) and so on.

The utility far outweighes the inconveinence. But you can get around most of the labor with a few simple plumbing tricks.

How many of you use a toilet? Do you refill it with buckets? ;)
Why would a large tank be any different?

Tom Barr