Reef safe concrete

[Reignfire]

Hello reef community! Ive been out of the hobby for about 6 years and Im currently building a new scape for a small tank. I want to pour a thin base that will be covered with sand for a more solid foundation. Ive searched looking for the right answer before posting but havent got a solid answer. Is this product going to give be a solid base thats not brittle and will be safe for my new aquarium? If not what do you recommend me using?

Thank you and very excited about being back!

 

[kharmaguru]

I know people have used this hydraulic cement:

https://www.homedepot.com/p/Quikrete-20-lb-Hydraulic-Water-Stop-Cement-Concrete-Mix-112620/100318534

If you want something aquarium specific, maybe Aquaforest Stonefix?

StoneFix Aquascaping Cement - Aquaforest

 

[Reignfire]

I have the e marco 400 from bulkreefsupply I used to cement pieces together. I have a lot left over and tested it and its very brittle. Might try mixing in some rubble to see if that helps

 

[Dr. Reef]

Jurassic Gel 4540 Reef Adhesive works pretty well

 

[shred5]

I have the e marco 400 from bulkreefsupply I used to cement pieces together. I have a lot left over and tested it and its very brittle. Might try mixing in some rubble to see if that helps

I have been using the E-Macro stuff and it is nice because it has the Liquid Polymer Additive that mixes with it and dries much harder.

I have used pretty many of the others and it seems better and it is icp tested. Some cements can leach aluminum.

I would guess though that E-marco is just Portland cement and I have heard the hardener is Acryl 60 mixed with some water...

 

[Reignfire]

What do you guys think? This is about 20 lbs for a 20L or a 29 gallon

 

[kharmaguru]

What do you guys think? This is about 20 lbs for a 20L or a 29 gallon

Beautiful.

 

[Reefing102]

Looks really good! Only thing is the right rock may be a little high for a 20L

 

[Reignfire]

It’s about 8.5 inches tall so should be good to go, thanks though I did consider that!

 

[HumbleFish]

@Paul B This is right up your alley

 

[Paul B]

I built most of my rocks because I can build them nicer than the rocks I originally collected by SCUBA diving.
I use regular Sakrete mortar mix and have been for decades. Some pieces are in my reef since the 80s.
I make my rocks hollow on PVC skeletons. I am not sure whats in hydraulic cement so I don't use it.

This large piece is the backbone of my 6' tank



Smaller pieces look like this




This is one of the bases under the rock that holds everything up off the bottom.