Nitty Gritty

I use a fairly simple setup. A float-switch in my sump controls a pump. When the water level drops the float switch turns on a peristaltic pump. The pump draws RO/DI water out of a 5g jug and "pushes" it in to a kalk reactor which then feeds water in to the sump. Ok, it may not sound simple but in practice it is. An even simpler set up would be a small pump in a 5g bucket that is controlled by a float switch. As for kalk there is several pros; it can keep your calcium level up & it can keep your ph up. The only real con I can think of is if you add too much too quick you can spike your ph.

I would suggest that you try not to dose kalk via yourtop off. If something goes wrong you can overdose kalk.

For Top-off I have 80l (20g) plastic container sitting above the sump (otherwise I would need a pump). This is filled by my RODI which is on a garden timer from the mains, so the RODI unit is not under pressure unless it is in use. I set the timer (which I adjust a few time a year) so that I am always about 1/4 full at the end of each day. I have a float valve in the sump, but I have also put a restricter in the hose to this valve so that I can only trickle feed RODI water. (For about a year I had a timer but found that I didn't really need to go to this expense and what I am using now is simpler).

I use 3 part dosing for my 1,900l (500g) system, (Ca-Damprid, Kh- Bicarb Soda and Mg - Epsom Salts). I just add the required amount daily, that is, I do not drip it, and I have not had any problems over the last 18 months or so that I have been doing this.

Me I use the diy ato from bulk reef supply. Has a double float switch in case one fails. I little assembly, maybe 30-45 minutes tops. I use a small maxijet, smaller that the 400, sorry I can't think of the number right off hand. I was using kalk with my top off but was having to many problems keeping my alk stable so I went back to just dosing equal parts of 2 part Ca and alk. Was having to many swings which was causing me to many issues with my sps. Check out Bulk Reef Supply, I think the diy ato was 29 bucks. I have had zero issues with it so far. I add my 2 part in the am when ph is at it's lowest, that will help prevent spikes. That is my .02

I use a gravity system with good results. I have a 5 gallon bucket remote from the tank with a 1/4" poly line plumbed into the bottom. The tube runs to a Kent float valve located in my sump. I have a low demand for calcium so i mix my kalk weak and let the bucket dose it for me. If my tests are running high i might skip kalk for a week. This system has it's flaws esp in this smaller tank, evap can cause me to add too much or not enough. But my tank is mainly Soft corals so it is forgiving. If i where to have more sps i would use either a pumped kalk reactor or pump from a bucket of kalk.

I am using a poor mans auto top off. works great, i just add water once a week for my 75 gallon tank, i use a 200 gallon salt bucket, drilled a hole about an inch from the bottom. put a float in the sump at the level I needed the water to be at. put the bucket above the sump and let it gravity feed, cost me in total, 8 dollars. works great. I added a link to a pic on my facebook of old bucket but if you want a close up pic let me know and i will send it to you. parts needed, 1 bucket, 1 float valve, 1 ro connector. and ro tubing.

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